This is where the fediverse is both powerful and a bit of a challenge to moderate. The best way to deal with these things is to be vigilant in sharing information that supports the contrary; since there's no real way to filter out bad information unilaterally (and even if so, I'd find that to be a dangerous precedence as who constitutes "good" and "bad" across the federated instances).
While the post was quite toxic towards the admins, the opinion of the user was done in what I see as exasperation at the situation without necessarily understanding the logic of these choices made for the beehaw instance as a whole; so there's an opportunity to redirect them to a different path or understanding. I'm aware that there are likely several others who share this opinion and may learn from this (just taking a moment to review some of the kbin.socal and lemmy.world threads on this subject shows this as a common concern). Moderation and intervention is more about systemic patterns of an individual's behavior that clashes with a community's ethos. Following the ethos of our admins, we take a measured response based on history and engagement.
As for now, things appear to have resolved through disengagement, so mission accomplished: we got the information out there and addressed their concern (and possibly inform other lurkers and the various instances that federate with us on this point).