It'd be possible to sit here and theorize about how bad RV was as a corporate overseer, and some of it is almost certainly accurate. That said, a lot of the talk about RV will always be a game of guessing and assumption, usually about the very personal lives of very real people. Meanwhile, I can directly point to the many ways in which Fandom has deteriorated since they first started to catch on around 2015, both in their own website design and in that of every website they subsumed along the way (RIP CurseForge.) No matter how bad RV may have been, there is zero possibility in my eyes that things will improve under Fandom.
This acquisition is a transparently-blatant attempt to develop more of a monopoly on movies/comic/games fandom than Fandom already has, while also eliminating no fewer than three of Fandom Wikia's few remaining competitors (Comic Vine, GB, and GameFAQs' wikis.) As someone who hates the now-inescapable refrain of bloated megacorps acquiring everyone tangentially related to their business, and also as someone who values immensely the Giant Bomb wiki as well as almost any wiki not powered by Fandom, I fail to see a single angle of this that isn't just bleak.