Set up forwarding in Gmail to your new address.
Then, whenever you log in to a website or app with your Gmail, take a moment to change it to your new address. In a few weeks, most of your important accounts will be covered. In a few months, almost everything you still actively use will be done.
I did this ~5 years ago and the only thing that still arrives at my Gmail is spam.
You can mitigate/speed the process using your password manager too.
I still use a filter in my email so that if something comes in under my Gmail, it gets a special tag that I can filter on and treat those as a todo list. Rarely happens beyond the occasional Google Meet connection.
It probably doesn't matter, but it made me feel a little better because that way Google wouldn't have direct info on to which email/domain I transfered (ignoring other Gmail contacts that start emailing me at my new address(es) ).
Making a new local account on your machine is a good first step.
This looks like perfect case for change of email, since lot of these accounts can be moved out from Gmail by changing the address that email is forwarded too.
Looks like all this hassle with generating a new email for each service pays for the second time (by ease of changing the main mail), in addition to spam and privacy protection.
You can buy a domain name for like $10 per year; I recommend getting it from porkbun.com.
Cloudflare.com is good too, EXCEPT if you buy your domain from them, you'll be required to use their nameservers until and unless you transfer your domain elsewhere (which you won't be able to do for a while). Though to be fair, their free DNS is good and lots of people use it anyway. It makes email setup slightly more complicated, but it's still doable.
Spaceship.com also has a pretty good reputation, but I think their customer service isn't as good, they're quite new, and they're owned by Namecheap (a bigger domain registrar with a much worse reputation).
Whatever you do, DO NOT buy from GoDaddy. Do not even search for the domain you're considering on GoDaddy. Literally any option is better than GoDaddy.
By far the most reliable TLD options are .com, .net, and .org. These will look relatively trustworthy for email, and the price stays very very stable from year to year. If you don't want to think about it, just get one of these. You can even still find single dictionary word domains for .org or .net relatively easily.
Do not buy any domain marked "premium". This means the owner of the TLD can change the price at renewal as dramatically as they want, for any reason (e.g. if you have a website hosted at that domain that becomes popular). Your $20 per year domain might suddenly become a $300 or $3000 per year domain for no reason but greed, and you wouldn't be able to do anything about it.
Non-premium nTLD's (.club, .horse, .rocks, .theater, etc) can increase quite dramatically in price, BUT the price is required to be set the same for all domains using that nTLD, so they can't target any individual person for having a successful website or whatever. Also, you can pre-buy up to 10 years, which locks in your price for those 10 years. I'd still not recommend them for a primary email, but it's better than buying a "premium" domain. Just be aware that the yearly price might unexpectedly increase in the future.
Some country code TLD's are also good, but for email, probably stay away from the ones that spammers like to use.
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Anyway, what I actually originally meant to comment about is: if you set up forwarding from gmail and don't check that account regularly anymore, I recommend setting up a gmail filter rule that forwards all your gmail spam to you (their regular forwarding setting leaves it out and just sends it to the gmail spam folder). It's a little annoying to have to re-flag some of the spam as spam in your new email, but gmail has a habit of marking non-spam as spam for me, and if you're not regularly checking that spam folder you can easily miss important email.
Seconding this. Tthis is exactly what happened with the .sexy TLD: https://www.reddit.com/r/Domaining/comments/uia8pc/sexy_tlds...
After a year or two losing Gmail becomes an inconvenience; after a few more years it is nothing. As everything is now on your own domain name you can switch providers without affecting anything.
That's what I did about 5 years ago and my only regret is not doing it earlier.
Pretty sure just moving emails would have take a lot less effort. I had the advantage of keeping the domain until I was ready to move, now imagine Google just turned it off one day and what your workload would be. I shudder to think about having to deal with that.
Imported all my past mail on day one, forwarding meant I had one inbox only, and I only sent mail from the new domain. A few gentle “please stop using my old address” conversations with family.
I got a custom domain. I still host it on google, because I know how impossible it is for small companies to have a reasonable program to deal with insider threats. Because of that, I think only one of the giant companies can realistically provide secure email. And the google app suite is great. Now that I pay for google workspace, there's support and appeals available, and if they ban me anyway, I still control the domain and can regain access to everything.
I have not been able to delete the old address, even after 3 years. There are some things like Google Fi that can only use a non-workplace google account. Very, very rarely, I still get an email that matters on it. But I got to the point where I could stop checking it in about 2 months, and now I look at it about once a week quickly, more out of habit than anything else.
The switch was annoying, but not "hard". It was worth it.
After a few years you'll notice you stop bothering to check your Gmail and you can delete it to close the address.
If you need motivation, skim the /r/GMail subreddit and see how many people are getting locked out daily.
I vaguely recall encountering a service that only accepted addresses from a whitelist of big providers (Gmail, Yahoo, Outlook, etc.), even @icloud did not qualify.
I've never once run into a service with such a restriction, but I can imagine someone being that short-sighted. I have seen services that only support "log in with Google or Facebook", which is comparably terrible.
Who? Never heard of them, and it sounds like there's a good reason for that.
make another mailbox (another provider - migadu, fastmail, proton, whoever) that has IMAP as well. (selfhosting.. is PITA. only if u really need it).
install some standalone mail-client - thunderbird, clawsmail, applemail, or k9 , aqua on android, whatever. Attach both mailboxes into that. Find out how to copy an e-mail from one folder into another.
Folder by folder, select all mails, copy from one mailbox into the other. Will take time.
(Beware, some clients (apple) will fuckup the mail-date, anything older than 5 years becomes 5 years old. or it shows like that. YMMV.)
i have made this multiple times, for 20+ years of mails...
What's the playbook for migrating away in this situation?
I switched to fastmail with my own domain.
Although I am increasingly concerned with its longevity since there's a non-zero risk that Proton might shut down SimpleLogin since Proton Pass has its own alias feature.
Current state of OIDC should be pretty much standard across most providers - it put it that devs need too make the push to support alt login providers for preventing vendor lockin in identity like were currently barreling towards in hardware/software.
You're right that having a vanity domain for your primary email address isn't for the faint of heart. There isn't any realistic advice for the average person because it's not for the average person.
Sure, you'll likely miss some emails, but otherwise it's safe.