You don't need to reinvent the wheel to have a "somewhat safe email". Just own a personal domain and host it on migadu, mailcheap, mxroute, Zoho or any other provider.
I've ranted about this before, but setting up or migrating semi-selfhosted personal services like that is a lot of hassle, even if you're used to cosplaying as a sysadmin.
Migrating DNS providers is a pain - recently done it twice. Transfer itself is reasonable with most providers. Importing/exporting a BIND-formatted zone file is sometimes unheard of, as is setting custom TTL; you'll have to go through a stupid form. One provider tries to hold your hand so tightly it won't let you set CAA with iodef, only issue/issuewild.
Migrating email is a pain. Yes! You can just point your MX elsewhere, and that is brilliant. You still want to copy over all your email, and given IMAP has won, if you don't have a recent backup (who does back up their email?), losing your old account sucks.
Fixing up your email clients is also troublesome. You can't just CNAME smtp.yourdomain.com to smtp.example.com, because that's nuts, so changing providers from example.com to beispiel.de requires a couple more dances; provider docs also suck, and email clients usually fail a dozen times before you can find the right incantation. You could set up your own autodiscover, but that requires an HTTPS server.
Yes there are providers that sell a full package and do all the initial setup for you, but that's not the point of owning your domain.
Yeah, I sometimes do sysadmin stuff for fun. None of this is fun.
None of these things are really that hard to do, and there are tons of tutorials on the Internet if you're not a sysadmin. I agree that these things are not "grandma can do it" easy, but they should be straightforward for anyone who has reasonably solid command line chops. Plus, they're all one-time tasks. Once you've moved over to your own domain and your own server/software, you're done--you don't have to do it over and over.
The official migration guide for Migadu invites you to use thunderbird and basically move all emails and folders from one account to another. No blame to them, but it's stunning that that's the best solution we have for migrating email
IMO email should not be an archival service. Everyone should be ok with losing all of their saved emails at any point. If it's important, save that information elsewhere.
The lock-in does have the bonus that it's practically impossible for someone else to take over your email address. Forgetting to update your credit card for renewal, long term afk/coma, death etc. are all issues with having your own domain and I decided to move away from that model.
It's the other way around in my opinion. With your own domain you own your identity. By ceding it to someone else you risk losing it at a whim of some algorithm or bot or by forgetting password, or getting locked out for some other reason.
The problem is that you can't own a domain, you only lease it for a limited time. If you fail to pay the lease, you automatically lose it, and someone else can automatically get it, and there's nothing you can do about it. Domain names are worse than email providers from this point of view, since even if you lose your Gmail account, Google will typically not give it out to someone else, at least for some time.
Your point that phone numbers and mailing addresses work in much the same way is true - but I don't think these have ever been quite as directly tied to identity as email is on the web.
Traditionally, for anything that's even slightly important, either your physical presence ultimately acted as your identity, or significant legal liability protected the non-physical identity (that is, if a court sends an important letter to you at some address, someone else who moved in to that address faces significant legal penalties if they open that letter).
Isn’t the same thing true of physical mailing addresses? If you don’t pay your mortage or estate taxes, you lose your physical mailing address. Yet people seem to have no problem considering themselves to be the owners of their houses and residences. Why should domains be any different?
Timescale, for one. If a lender wants to foreclose on your home, they'll usually have to go through a whole process, giving you a month or more of notification. During and even after this time, they'll often be happy to just take your money if you can come up with it, and they may be required to, depending on your jurisdiction's redemption laws. (E.g., my state gives owners an entire year following a tax sale to redeem their property. Some people make a whole business of chasing after redemption money.)
In contrast, many domain providers will resell your domain in a heartbeat once you miss a payment deadline. And then the buyer can do whatever they want with emails sent to that domain, since there's no such thing as identity theft when your domain is your identity. In the case of a mailing address, it's not an identity at all, which is why non-junk mail will also have a recipient line.
