This isnt really good arguments.
You still can access the cloud, unless there is some tech that allows your users to lock you out.

I personally do believe that your solution might be better than proton mail.

But trying to get privacy on email is inherently hard, since the protocol is unencrypted and has holes for metadata (like mastodon).

I personally dont think being full paranoid is good, trusting nobody.
One should simply limit their use of email in general, and should try to control their data.

When you say emails allow you to reset your password, that you can say is a problem with the services.

Services like firefox account,telegram,signal have protection against password resetting (ok not quite sure about telegram).

I personally use gmail for services that I dont personally feel are private. 

 This is not only email, but also cryptpad cloud (replace google docs) and XMPP.
Self-hosting XMPP or SimpleX is far more private and secure than relying on a random third party server.

While I agree email isn't that private to begin with, this protects you against passive AI surveillance to a far greater degree.  And email has a big risk of aggregating all information about you.

The real benefit of our product is getting all of these services on a single tiny VPS, so you get the most bang for your buck  

 Yeah I think it's a good idea. I absolutely hate setting up self hosted email, so if I needed to self host I'd definitely rather pay someone to set it all up for me. It's like the best of both worlds: you get the security of self hosted without the pain of having to do it. Bonus points, you get xmpp?

I personally dislike email, but the fact is you're stuck with it, and if you're all about your privacy and security, self hosting is the way to go.