Mostly because if I'm going to go through the trouble of maintaining a Nextcloud instance, I might as well use its calendar to maintain more control of my data. If Nextcloud gives me trouble down the line (as it tends to do in my experience) then I'll give Tuta's calendar a try.
I'm optimistic for Nextcloud though, the latest AIO docker versions seem solid.
Do you happen to know any alternatives for their email? Some security guy on YouTube was talking about how their email aliasing is better because if you lose a single email/password combo, you're not subject to any other breaches.
I mean I already use a password manager since I adopted KeePass like 15 years ago and use Bitwarden now, but I still like that concept.
Depends on if anyone you message uses proton. If they do, you can always get their pgp key and save it to thunderbird. If nobody you know uses proton, there is no benefit to their service over the above.
This is one of the reasons I will never fork over so much cash for a yearly subscription to anything. I pay monthly on everything I subscribe to, because you never know when that service decides, “Yeah. Fuck it. Let’s go downhill, full sprint!”