This is exactly why I only trust myself to do it. I almost lost my gmail account a couple of times in the past, and every time it was quite stressful. Since then, I use gmail as a backup email provider, than is, pretty much never.
Due to the way mail servers work, you have a couple of days to sort out your troubles before you will start missing emails. At worst, you can always buy Google for Work or some other SaaS and point your MX servers there.
Backup is always a hard problem, but I got to live with Hetzer Clould backing up my VMs, Hetzher Backup boxes as restic backup targets and a tiny Celeron server in the laundry closet for local backups.
In theory that makes sense, one thing I specifically omit as to why I stopped running my own service is in the past in a bout of paranoia due to the onset of a mental condition, I literally rm -rf'd my laptop, including a lot of files that were unrecoverable. Thankfully I didn't do this to my server at the time. Even though I've been stable for a long time, all it takes is a relapse (or even just a lapse of judgement) and boom your servers (and backups) become vulnerable.
I also don't trust that I can secure my systems and backups better than a company that dedicates itself to running a service for multiple users and have dedicated security/infrastructure teams. Sure I've never actually had an issue, but as with the anecdote of my friend, it just takes one failure. Also economies of scale helps with security; it is easy for an attacker to exfil or do damage to a smaller corpus of data (few to no customers [users]), than a large corpus of data across 1000s of customers.
I wouldn't trust a free service or a service that doesn't provide adequate support such as Microsoft or Google, but there's obviously a good selection of email providers out there that do an excellent job, much better than those self-hosting because they work with economies of scale.
This is exactly why I only trust myself to do it. I almost lost my gmail account a couple of times in the past, and every time it was quite stressful. Since then, I use gmail as a backup email provider, than is, pretty much never.
Due to the way mail servers work, you have a couple of days to sort out your troubles before you will start missing emails. At worst, you can always buy Google for Work or some other SaaS and point your MX servers there.
Backup is always a hard problem, but I got to live with Hetzer Clould backing up my VMs, Hetzher Backup boxes as restic backup targets and a tiny Celeron server in the laundry closet for local backups.