There is even a much larger problem here other than not being able to self-host your own email. The issue is that large providers and large companies have no accountability. No way to ever have a conversation with an actual person (email or by phone) to resolve a simple problem or mistake in an algorithm or automated process (or even a manual process if that's what it is). Canned replies not reply to follow up question not a care in the world or a conscience. And the fact that the service is free (to someone) does not mean a company should be able to so easily do what they want and cause aggravation to others.

And it happens even with paid services at large companies.

That is not 'just business' and has never been the way business operated pre-internet except in a few super rare (and perhaps rare monopoly) situations.