Decentralization was a thing back in the 1990s and 2000s with all of the little message board communities out there. I think people desire centralization without the drawbacks of control going to a small group of people so that's why we have the fediverse.
Like all this is more of a move back to how the Internet once worked. It's nothing new (at least to those of us who grew up with the Internet in the 1990s and 2000s).
Also, I want to add something: Beware of people fetishizing the fediverse as a cure-all to all or most of Big Tech and social media's problems. Remember, the technology is rarely ever the problem, the humans are. So long as humans remain really clever apes, you are not going to solve hate speech, spam, or outrage.
In fact, it seems like outrage about Reddit is currently driving the majority of engagement on Lemmy so far, even though it's been three weeks since the API protests. Just look at all of the most upvoted posts here. Discussions about how bad Reddit is currently and how Lemmy/fediverse will save everything and make everything good. On social media, moderation is still extremely important, and from the snark and trolling I've seen here and there, I hope the mod team doesn't fall behind and I hope that the Lemmy developers create better mod tools, because if Lemmy does blow up, expect bots to show up. Expect propaganda. Expect automated trolling. All this shit hit Reddit as it got more popular.