Emperor Palpatine is even named as such in the first two Star Wars films let alone given a backstory.
He's just called "The Emperor" thruout the original trilogy and only actually shows up in the same movie
he got killed off in: Return of the Jedi.
If you wanted to know what Palpatine's name and backstory as a Senator, you had to read the novelization of Star Wars.
We didn't find out Palp's deal 'til decades later (unless it was fleshed out in books that I don't care about).
But the fandom is now angrily demanding stuff it didn't get the first time around, because they got so used to the Expanded Universe and the Wikis and the whatnot that they forgot that nearly all that stuff they love so much was added after the fact years later and was never in most of the movies.
That was the main problem of the prequels, they spent hours answering questions that a general audience never asked and didn't care about.
I could have lived my entire life happily not knowing who built C-3PO or how the O.G. Jedi pick their candidates.
As some point Disney is going to have to make the same decision that Paramount made with Trek: there was decades of canon that only Trek fans care about but nobody else does.
So they kicked all the old continuity and let the Trek fans either like it or lump it.
Do you make Star Wars fans happy or do you make a modern movie audience happy? Maybe you can't do both. People aren't mad at this movie for a failure in craft, they are mad because their particular area of fandom isn't validated in some way.
The grumblers who bitched about the last movie got what they said wanted: surprises and a swift kick to the junk of the status quo.
The heads talking about Grey Jedi and Jolee Bindo and how the Jedi suck and "why is it always Skywalkers?" also got what they wanted.
Watching them all go "We didn't mean it like THIS!" makes me laugh, frankly.
First off, you’re making an assumption that a lot of the fans who have issues with the lack of info on Snoke read the EU books or comics. The number of EU fans are a small segment of Star Wars moviegoers. Admittedly, I am one of those people, but I can’t say that’s everyone. TFA did make him this mysterious person that raised questions, as well as about Rey’s parents. Her search for who she was, was a big part of both TFA and TLJ so I can see why people would feel unsatisfied about not getting those answers, or Johnson flippantly saying those answers don’t matter.
I disagree with you about the crux of the issue with the prequels. It is a fair point that the prequels likely didn’t meet with expectations, especially for old fans who had imagined what the Clone Wars might have been like before we actually saw them, but I see the general issues with the prequels as one of quality, not one of story. People were very excited aboud the Phantom Menace and even though there was less excitement for the other prequel films, both still made tons of money (the main argument being used to silence TLJ critics).
I think you present a very good take on the question facing aging franchises, but I also feel it’s a false choice. I think you can honor the past and honor continuity (and canon Star Wars films have a lot less continuity than live-action Star Trek does) without crapping on the fans. If you can respect what came before and retain the spirit of the franchise I don’t get why that has to be an either/or situation. And Disney/Lucasfilm has decided we are going to crap on the old fans to some extent. So if you do that, if you attack the root, and not bring them along by supporting it, the tree is going to fall. Disney has not removed the trappings of Star Wars-the First Order/Empire, The Rebellion/Resistance, TIE Fighters, X-Wings, The Force, lightsabers, but is that what makes Star Wars solely? Or is it the characters? Removing those old characters (and often in a disrespectful way) and then barely doing anything interesting with the tropes is a hollowing out of Star Wars.
Star Trek has also run into some problems, but even Discovery, which is getting hit by some fan backlash (some of from the anti-“SJW” crowd, some from continuity hawks, some from people who don’t like the new focus on war, violence, and some who don’t like that the show is on CBS All Access) it still pays more respect to what came before. Each incarnation of Trek lets the old heroes remain heroes. It doesn’t mean they are perfect, they aren’t, but Trek has found a way to honor the past while moving forward far better than Star Wars has.
And there’s this disdain for nostalgia while also reaping tons of money from said nostalgia. It’s not the casual fans who are buying all the ancillary material, who will watch a Star Wars film multiple times, who will keep interest in the franchise going in the lean months between films or shows, and that goes for Star Trek or basically another other big franchise as well.
As for Snoke and the Emperor, you’ve already mentioned the points I have that I feel undermine that argument. It’s hard to compare the first three films in a 40 year franchise to the eighth film. By this time we have seen Palpatine’s backstory fleshed out a good deal in the prequels and in novels, comics, so why wouldn’t fans expect that there was more to Snoke than what we got? Why try to do a clone of Palpatine in a sense? How original, fresh, and bold is that? Why recycle that, like they recycled so much in TFA? It just shows a lack of vision and creativity to push the story forward. And the EU does offer some ideas about how to create different villains or even how to handle the Empire post-ROTJ that didn’t need to be dismissed, since TFA likely borrowed from it anyway.
I didn't care about Grey Jedi, though that's where the film was seemingly going with Rey and Kylo, so why not? That builds on the mythology in a more coherent way than we got in TLJ. Instead of just having it be about one of Kylo's needy mood shifts or Rey's insecurities about her parentage. Those can be driving it but at least the Grey Jedi thing provides something concrete to either hide their true motivations behind or to stand on.
I did want Rey's parents to be 'someone', the 'nobodies' thing isn't horrible, but it's not like we haven't see heroes from humble origins before in Star Wars. I did want Snoke to be Plagueis but I also liked the idea of the Prime Jedi as well. That would short hand tell me that this guy is a major deal and easily explain why he was able to build the First Order and bring Ben Solo to the dark side. Even Johnson provided some rationale about why Luke went into exile, so the idea of providing backstory and motivation isn't completely anathema to the new Star Wars. I do think the problems with TLJ also had an origin in the poorly thought out TFA. That did rely on nostalgia and solid film making, but there wasn't much there. And it's odd that J.J. Abrams, who wasn't a Trek fan really, honored Trek with his 2009 film in how they handled Spock and made him a more integral part of that film in passing the torch than how TFA and now TLJ handled it's original heroes. There are people who disliked the Abrams films, for a variety of reasons. (I wasn't the biggest fan of Into Darkness because of the use of Khan and how he was cast, to be honest), but the treatment of Spock Prime is something I haven't heard people complain about much. (Though I did think he was shoehorned into Into Darkness. And that film did him a bit of a disservice, but I digress.)