One issue with emails is that it's actually very difficult to self host email servers now as most of the bigger servers would automatically block unknown servers due to spam

Pretty much the entire bdsm community everywhere was outed on Facebook because folks carried cellphones to events and Facebook started suggesting friends to one another. Fifteen years ago privacy was sacrosanct and no one shared real life names unless they were very close. Now there is no point to trying to keep your identity secret and it sounds silly to introduce yourself as "Master Darkness" or whatever. I mean it sounded silly then, too, but everyone understood the necessity and it was situationally appropriate.

That is the danger of these large corporations. They aren't looking to serve the broad community - they are looking to exploit our social graph for profit regardless of the destruction in their wake.

I'm not against corporations wanting to set up their own instance for their own employees for them to interact with the Fediverse. I'm against data-collection, targeted advertisements, and corporate control.

I'll answer with a blog post by a dissatisfied sysadmin: https://cfenollosa.com/blog/after-self-hosting-my-email-for-twenty-three-years-i-have-thrown-in-the-towel-the-oligopoly-has-won.html

Email is now controlled by a handful of big corporations, all of which data-mine all of the emails passing through them. You can't run your own email server any more; if you do, emails you send from it will almost always be rejected.

Email is a cautionary tale of why getting bigger corporations involved is the exact opposite of a good thing.