a few companies (mainly those in the open-source space) run their own Mastodon instances, though this is more common for FOSS organisations

As far as I'm concerned, Corporate PR can stay nicely fenced off over on Xitter.

Keep all the bullshit in one far corner, over there, in the distance, behind the big wall, topped with razor wire.

I mean, lots of local and/or small services announce disruptions on Twitter only. Many of those have separate news/service status pages on WWW, and yet neglects updates of those. Possibly because users without access to Twitter aren't worth informing.

IOW, Twitter still is a social data infrastructure, like road or tap water. Something that the society depends on, that also ain't nobody paying for it, something that only makes sense at-cost max or at a loss.

I think that was always a fundamental problem with Twitter as a for-profit company. Surely it handles a large amounts of important communications, that are also not so exploitable or monetizable, ethically or not, just fundamentally.