So for newcomers to the fediverse (also, hi!), mastodon has gone through debates and events too. People my differ on this, but I think the whole phenomenon is just a part of the fediverse and that it's fundamentally a good thing.
Where it causes drama or friction, I think it is essentially a different kind of friction compared to what happens on big-social platforms. And while it can have its problems or be mishandled, the problems, IMO, reflect real-life social dynamics more, and are therefore healthier than being subject to and at the whims of big-corporate overlords with many more interests other than true cultural and human engagement and interaction. Sometimes, people and whole groups of people just don't want to know each other. Free-speech and political discourse ideals aren't the catch all analysis here. This isn't the news papers or an academic journal, it's social media.
Bubbles are problematic but so are firehoses and incessantly unpleasant social interactions ... grouping and excluding is what we do ... it helps to match our finite minds and lives to the magnitudes of reality.
Beyond this, I think many are just not accustomed to real-life human dynamics playing a more structural role in their major social media life. There's an adjustment that needs to happen. And this goes both ways, for those against and those in defence of defederation actions, where attacks on defederation may miss the point and defenders may not see that there are sometimes better ways to manage problems.
Many of the attacks of defederation are along the lines of "this will stifle growth". I get it, and I've said the same myself elsewhere. But, one, not long ago no one thought any of this would "grow" and yet here we are, so maybe save the prognostications and try more substantial and constructive critiques. And, two, much of the above about transitioning to different modes of online socialising necessitates friction, where the fediverse is not simply your substitute for big-social waiting for the special moment you decide big corporations have crossed your line, rather, it's a different system, problems and all. Now, by all means, critique the fediverse (I sure do), but, I would recommend doing so with some of the above as part of your frame of reference.
For my money, the biggest problem right now is account mobility. Your account is stuck and limited to an instance. Mastodon has migrations but it's really just importing your settings and followers to a new account on a new instance rather than truly moving your account to a new host. This is baked into the current structure of the fediverse. Instances are first-class citizens, users are second-class. It is truly accurate, though somewhat pejorative, to use "feudal-verse" instead, because that is actually what it really is.
In terms of defederation, the problem this causes is that you can find yourself at odds with the federation policies of your instance and want to leave, which is obviously a PITA. More deeply, it's hard to know the federation policies of an instance before you join, or how they'll respond to some situations, so events like beehaw can be a little "shocking", and sometimes hurtful, because you find yourself labelled by your instance when you in reality have little alignment it, at least on the matter at hand.
Thing is, belonging to an instance or a community of some sort, finding a "home" of sorts with a group of other people, is probably a good thing, in line with my comments about healthier and more "in real life" dynamics. The issue is that instances and us being forced to join them is somewhat arbitrary, and once you end up having multiple accounts, just a PITA and ultimately bad UX.
What the fediverse really needs, IMO, is both grouping/community mechanisms and for our accounts and their hosting to be decoupled from these groups/communities.
Lemmy/kbin and the threadiverse as a whole do well in this regard by having sub-reddit/forum like structures. Mastodon and the microblogs struggle as they are quite bad at communities (as the BIPOC communities found out it seems). But, as it stands, the threadiverse still couples community hosting with account hosting, and so we have the beehaw defederation issue (which I should say is interesting to see as communities or reddit-like structures haven't been popular on the fediverse until now-ish).
Technologically, my suspicion is that this whole fediverse thing goes to another level once a coherent protocol provides for optional independence between account hosting and community hosting and, arguably, independence between the prior two and platform format. We have "self-hosting", but at the moment it's a bit of a hack, still binds you to platforms and hardly provided as a convenient service (check out Spacehost, an upcoming service for this: https://spacehost.one/).
I wonder about self-hosting scales and suspect it's awfully inefficient, and so, technologically, I suspect some hybridisation of the architecture is required, where the whole web2.0 idea of user->server->platform just melts away.
In reality, the only real innovation of the fediverse is to parallelise the "server" part user->server->platform so that a single user on a single platform can be achieved with horizontal scale and a distributed work load.
user->server->platform
\-server-/
\-server-/
This has the effect of FOSS social media being a thing (here we are and it's awesome TBH), but isn't really revolutionary from a user perspective. Once multiple platforms communicate over the same protocol, it starts to get revolutionary, but that's only started as anyone who's tried to mix mastodon and lemmy can attest to.