All the new marvel stuff is poor as well. There seems to be a focus on more rubbish characters and possibly a focus on trying to make the franchise more diverse but a real lack of focus on actually writing some decent shows.
I'm not sure that Star Wars was ever all that, really - if you take out the nostalgia of watching as a kid.
I loved the original trilogy, but then I was 1, 4 and 7 when they came out, and RotJ was the first film I (remember) seeing at the cinema.
Prequel trilogy was definitely a bit ****, and only looks any better in retrospect because the sequel trilogy managed to be even worse (he says, I still haven't watched the last one - and don't intend to).
As for Marvel - I'm not sure if that's Disney's handling, franchise fatigue, or that they're going too comic book, with far too much handwaving, ignoring of precedent and fanwanking required to make sense of anything. They've always had those elements, but they've been ramped up to 11. They've also always had mishit films, currently though, all the films are mishits.
Once you start using "Quantum" to explain anything you can't be bothered to right around; convenient time travel, and multiverses (and multiverse travelling) then you start losing your audience. And that's not even bothering with the "He's not a god, just an advanced alien" => "Oh yeah, he is actually a god really, and can hang out with all these other gods as an equal" => "Oh, and he can give his godlike powers to absolutely anyone, at any time of his choosing", then... **** you, really.
They did ridiculously well building up a coherent (ish) story over a decade, with a huge partially integrated cast, leading up to a story climax. Then they should have rolled over, had a ciggie, and fallen asleep. But I think that's because the story was done, rather than because Disney.
Of course, they could always have gone away, acquired Fantastic Four, and X-men; done them for a bit, and reboot the MCU afresh in a decade's time.
I've given up on both franchises; but I'm not convinced it's "because Disney"