Stop allowing email providers to control the domain of your email. Buy a $10/year domain and point it at GitHub pages (so it gains some trustworthiness). Send your email to that domain, and point the MX records at a mail provider (Fastmail or GMail or ProtonMail, doesn't matter).
I own several domains, and I have two valid email addresses at two personal domains hosted with a small US hosting provider, but I don't want those to end up in spammer lists so I use them sparingly. For a main email address I'm better off with a large email-focused provider that has tools to handle all the spam that builds up from an address used for online purchases and forum/social accounts, and as I mentioned Fastmail has the absolute best tools for managing all of that. Gmail is not an option, nor Microsoft.
When people say use your own domain, they mean use your own domain at the email provider of your choice. You don't miss out on any of their tools by using your own domain.
I get that, and as I said Fastmail has the best tools for managing email, so since none of the other major email providers have the features I want it wouldn’t do me any good to move my own domains to any of them. I’m sorry if that wasn’t clear in my previous message.
