Become unbannable from your email

Forwarding mail is problematic. If you forward spam, your spam score can increase and suddenly you‘re on a blacklist.

Also when you pick an email provider, pick one with a good privacy policy.

Counterpoint: I lost a domain when a registrar went out of business, and another when a registrar bumped the price 10x and refused to give me authenticode unless I physically show up to their office. Sure, I cheapened out and used shady cheap registrars, and this all happened a while ago so things are probably more regulated now, but for comparison I never permanently lost access to hosted email. (Losing access temporarily is another thing, Google likes blocking me from my own account when travelling.)

"How to become unbannable"

Step 1 : go with the one company that's known worldwide for abusive & permanent bans with no recourse.

This post is a bit too generic, but it's true that using your own domain for mailing is the best solution to avoid getting locked out. Although you need to pick a good registrar, too...

There are online services where a bad actor can enter your email to automatically sign you up for hundreds, thousands of marketing emails. In the event that that happens, given that you have full control over the domain, you could just divert whatever @yourdomain.com to a black hole. What will happen when email attacks become more advanced--to the point of signing up thousands of different @yourdomain.com? What strategy would one have then? You would most certainly have to part ways with that domain.

The author makes a good point, your email address is (arguably) more important than your home address. Perhaps there already are, but I hope for better safeguards against these kinds of attacks.

Over the past few weeks I've been systematically migrating every one of my accounts to a domain under my control.

During the process I've been marking them in a spreadsheet with their 2FA status (no 2FA, TOTP, security key, etc.) and adding their passwords to a password manager.

This is all in case I ever need to go through the migration process again for whatever reason, or if I lose/break a Yubikey, I will know what I'm signed up for, and will know where to enrol my new Yubikey(s).

It really is a massive hinge for many people that isn't even really considered, most people's entire digital lives would be uprooted if they lost access to their email for whatever reason.

Thankfully that doesn't really ever happen to most "normal" people to my knowledge, since most just use Gmail, but I know it can and has happened through account bans or such.