Because people try to justify that their not liking it is something other than personal taste. It's not enough to say "I looked at the new rulebook and it's not for me.", they have to show objectively that WotC is being deceptive and manipulative with them so that their refusal is framed as an act of heroic rebellion. The narrative is that WotC is Evil and therefore cannot be capable of anything good, so even if the 2024 books are good, they must find the conspiracy that makes them still evil (they are secretly 6e. They are built for Sigil/MMO play, they are only designed to invalidate the old books and make you rebuy everything).
It's one thing to say "these books aren't for me and my group, but I wish WotC the best of luck." But people are actually rooting for WotC to fail. And frankly, I think it speaks to the fandom in general that "no D&D is better than bad D&D" has become a mantra for the hobby itself rather than a way to handle abusive DMs.