I can see where you get that... but I don't really agree with that premise, that the events in ep IV-VI don't matter. We see the same sorts of patterns in every day life - either in smaller, personal things (people have a failure, and withdraw from a community or whatever, rather than accept it for what it is - that they're not "perfect", etc), or in larger cycles where evil is seemingly defeated, but later re-emerges in a similar form. Fiction necessarily magnifies things for dramatic purposes, but you're basically just describing normal struggles of life writ large.
Specifically in the SW universe, there's been about 30 years of relative peace under the New Republic that we basically don't even see in the big movies (the time between ROTJ and TFA). It doesn't appear to be a perfect time (I'm not completely up on canon and all the stories that occur in that timeframe), but neither were the "good old days" of the Old Republic, either. The galaxy doesn't know those 30 years without IV-VI, and things aren't set up to eventually eliminate Palpitine and for balance to return.
That said... you might be right about Kenndy, et al at Disney, wanting to disrupt the previous arc and method of story telling - and it's quite possible she and others at Disney are responsible for the "wokeness" in TLJ as much as Johnson. It wouldn't really surprise me if that were the case. Either way, it's clear that no one had over-arching creative control over the SW universe. Otherwise, we'd likely have a much different episode IX.
My point about VIII being terrible, though, is more centered around the fact that you could leave half of it on the edit bay floor and have a movie that tells the same effective story in one hour just as well as the movie that appeared in theaters - and that represents terrible story telling regardless of plot, character arcs, etc (ie, it was a terrible movie even for pure movie's sake, and not just SW universe purposes)
But... ??