Problem is with the way email security is going now, it's entirely possible in a few years, if your domain/provider isn't an established one, it will get blocked by others.
I've had a few domain just straight up block some Tutamail emails.
But here's the other issue: Proton and Tutanota are both not going to make it easy on you to move your mail.
I believe this is already the case; domain reputation is weighted pretty heavily by Gmail and others, so it will take some months before you’ve established enough rep. Following SPF/DMARC/DKIM is crucial, followed with time your domain has been registered and typical outbound volume from your domain.
I moved away from Tuta, and while getting my mail out wasn't as straightforward as with regular mail services, it also wasn't hard.
Proton offers an IMAP bridge, which will let you use any IMAP client to download your mail and then transfer it somewhere else.
Problem is with the way email security is going now, it's entirely possible in a few years, if your domain/provider isn't an established one, it will get blocked by others.
I've had a few domain just straight up block some Tutamail emails.
But here's the other issue: Proton and Tutanota are both not going to make it easy on you to move your mail.
I believe this is already the case; domain reputation is weighted pretty heavily by Gmail and others, so it will take some months before you’ve established enough rep. Following SPF/DMARC/DKIM is crucial, followed with time your domain has been registered and typical outbound volume from your domain.
I moved away from Tuta, and while getting my mail out wasn't as straightforward as with regular mail services, it also wasn't hard.
Proton offers an IMAP bridge, which will let you use any IMAP client to download your mail and then transfer it somewhere else.