Here I’m a bit in two minds, sure it’s difficult to SELF host email, but in practice it isn’t because there are hundreds (Thousands?) of hosting options to choose from where you can choose your own domain etc. for the low price of basically-free

I would prefer to limit this to actually hosting it on a machine you control. We don’t consider redirecting a custom domain to a subreddit “self-hosting”, do we? Yes, there are many email providers out there but that’s more like existing lemmy or mastodon instances and not like hosting your own where you have full control over your data.