Comment by AnonC

Same here. I don't want a custom domain for certain things, and Posteo (posteo.de) was good. Posteo increased the mailbox storage to 4 GB recently and the default number of free aliases too. I'm satisfied that it's run by a team and not by one person (the low bus factor mentioned above). At EUR 1 per month, it's way cheaper than Fastmail for multiple mailboxes across family members and provides a lot more value, IMO.