I don't need a custom domain anymore and I find it trivial to change email addresses. I can use 1password to locate accounts, easily migrate, apply a tag, and work through the change over a few hours. I typically change email every 2-3 years and it serves as a good way to review security settings/change passwords. Modern email providers have mailbox porting tools, and they work fine. I use to like having a domain, but dunno, for a privacy nut, seems more secure to not use one.
I was being a bit pedantic but ... a domain registrar could be an attack vector, its not as anonymous as something like proton/tutanota, not beholden to ICANN, if you use an alias related to your domain it could be tied to you. If I give up the domain in the future, it could be used against me in a social engineering way.
