If I'm being honest, I've come to realize that I'm actually just not that much of a Star Wars fan. If this surprises you, given that I've apparently put so much time into Star Wars TTRPGs and into this website, well, it was a surprising realization for me as well.
When I really step back and think about it, out of the entire collection of all the Star Wars media I've ever consumed, I can only say that I truly like two movies, plus a couple of old video games that I haven't played in years. There were some things (e.g. the prequel films) that I liked a lot as a little kid but that even with all the nostalgia in the world I'm just not able to appreciate much anymore, and there are other things (e.g. most of the fifty-something Star Wars novels I read as a teenager) that honestly have just never been very good. I have a lot of lore knowledge tucked away in my head still and a lot of lingering feelings from the ten-or-so years I spent as a diehard Star Wars fan, but for several years now I haven't felt any active connection to either the fandom or to the franchise itself.
Which then begs the question: Why have I invested so much time in this homebrew Star Wars TTRPG? Why use a science fiction franchise that I'm pretty sure I don't even like that much?
Likely due to having spent all of my childhood so invested, I feel very at home with the conventions set by Star Wars, in terms of both setting and genre. But it isn't just me. Star Wars is one of the most, if not the most, popular and familiar science fiction franchises in the world. Not everyone has seen Star Wars, but everyone knows what it's like. Star Wars defines ordinary people's conception of the science fantasy space opera genre more than any other piece of media.
There are other popular examples of space opera, Dune for example, that have a pretty unique feel to them. Star Wars, on the other hand, is perfectly generic. Partly this is from the fact that Star Wars had such a profound influence on the things that came after it that it now feels almost like the average of all other modern science fiction. I would guess that it also helps that Star Wars as a franchise has played out through many different types of stories told by many different authors, such that it doesn't have any particularly distinctive 'personality' to it that can be easily singled out.
As much as I like Dune, I wouldn't really want to run a TTRPG set in the Dune universe, because I'd be faced with a problematic choice: Either make my TTRPG follow the specifics of Dune's tone and setting, which would feel restrictive, or else use Dune as backdrop and inspiration while leaving myself free to explore in new directions, in which case the game would most likely end up not feeling like Dune very much. In contrast, Star Wars works well as a TTRPG setting because of how universal and generic it is. It's easier to create my own game and tell my own story while still having it feel like Star Wars because lots of things feel like Star Wars, and Star Wars feels like lots of things.
Going even further along on the spectrum of universality, though, it's worth talking about why I don't use some purposefully generic science fiction TTRPG system/setting, such as Traveller, or make my own setting fully from scratch. I do personally like Traveller a lot, both for the elegance of its ruleset and for the flavor of its setting framework. That said, though, using a less familiar barebones setting (or a custom setting) is a lot of work, both for the GM and for the players. I'm certainly not opposed to worldbuilding and coming up with lore for a new setting, but there's something to be said for the fact that by just saying the words "Star Wars" I can convey all someone really needs to know about the boundaries of a story or game. (Faster-than-light travel? Yes. Time travel? No. Political intrigue? A little bit. Psychological horror? No, not usually. And so on.) Additionally, even if I were to set out using Traveller or a similar framework, or to make things up entirely by myself, I suspect I would end up pulling a lot of the genre conventions and tone from Star Wars anyway just due to how much influence it's had on me over the years, and by the end the TTRPG would wind up feeling a lot like a Star Wars game regardless.
If you are a big Star Wars fan, or especially if you had been a fan since childhood or are familiar much with the expanded universe, I want you to try to step back for a minute and think about Star Wars with fresh eyes, to see it the way a person who has never heard of Star Wars would see it: The magical telepathic/telekinetic energy field is called "The Force". The way the good guys use it is called the "Light Side" and the way the bad guys use it is called the "Dark Side". The characters shoot at each other with "blasters". The spaceships fly through "hyperspace" using "hyperdrives". The main character's name is "Skywalker".
My point is that, when looked at objectively, Star Wars is silly and campy and whimsical, moreso than I think a lot of hardcore fans realize or would like to admit. There is a tendency among fans to treat quality cinema like The Empire Strikes Back as the "true" Star Wars, and to write off the embarrassing parts like Jar Jar Binks and the Holiday Special as horrible little accidents staining the franchise's legacy. I personally think it's not too hard to argue that in reality it's the other way around; but also, regardless of what Star Wars' "true" tone is, for my purposes as a TTRPG player it's good to be able to draw on the setting's whimsical aspects.
In my experience, tabletop role-playing games always end up being sort of goofy; a campaign's setting or background plot might be fairly serious, but the day-to-day game experience is always just kind of silly (and if it somehow isn't, it probably isn't as much fun for the players). It isn't strictly necessary for a TTRPG setting to have this whimsical attitude built in (and I think in practice, the setting and also the GM often end up playing the role of "straight man" for the rest of the group), but I do think that having a game setting that matches the tone can be helpful.
Star Wars fits well with what I think of as the ideal TTRPG tone; it doesn't take itself too seriously, but at the same time it doesn't make fun of itself either or drown itself in irony or tongue-in-cheek self-awareness. Star Wars (the old Star Wars at least) is just straightforwardly earnest in its over-the-top space opera cheesiness, in a way that's difficult to find examples of in modern cinema. It has exactly that spirit of pulp fiction adventure that so many classic-style TTRPGs try their best to capture.
Prior to the 2012 Disney acquisition, the Star Wars expanded universe was pretty notable for how many different sources and creators it drew from. Established canon included movies, TV shows, novels, encyclopedias, radio dramas, comics, role-playing games, video games, etc. There were several examples of lore details from secondary canon or from fan works later being taken up and incorporated into the main movie canon. There were certainly some contradictions and inconsistencies in the canon, but on the whole the Star Wars universe developed a relatively robust and self-consistent timeline without too much in the way of central authority.
Furthermore, especially after the prequel trilogy came out, it was pretty commonly understood by fans that the bad parts of Star Wars were bad largely because of George Lucas, while the good parts were often good in spite of him. This meant that Lucas wasn't revered as the canon's spiritual authority to the extent that creators of a lot of other fictional universes are.
Disney's choice in 2014 to discard the majority of the expanded universe as an obsolete 'Legends' canon was upsetting to me and to a lot of fans. The silver lining, though, is that by abandoning so much lore and alienating a lot of the diehard fans, Disney helped to separate Star Wars as a corporate media franchise from Star Wars as a shared fictional universe and cultural phenomenon. Disney owns the legal rights to publish and sell new material for the franchise, but Star Wars is a much larger thing than those legal restrictions. The fact that Star Wars now has multiple contradictory timelines and that any fan can more or less choose for themselves what aspects of Star Wars are canon, or add to the canon themselves, and have their decision be no less "correct" than George Lucas or Disney, is in my opinion one of the best things about Star Wars as a science fiction setting. No one really owns Star Wars, which means everyone owns it. The stories that people might create together in a TTRPG campaign are as legitimate as any others.