In principle, you could store your Bitwarden database on a public torrent at no risk to your security :)
So, if you do trust the Bitwarden software in the first place, self-hosting it shouldn't be any more dangerous than using the managed service, because the server security isn't really a critical part of the defence model. And self-hosting allows you to build from source, if you're inclined to paranoia (Even though the worst a malicious server could do is delete your database).
That said, I have still bothered to set up strict fail2ban rules on my BW instance, because why not.
Unless you use the web client, and a lot of Bitwarden's functionality is only available via its web client (including critical functionality like changing your master password).
Reading between the lines it sounds like being able to build from source or see and install the source gives some assurance you can’t get via third party and the strong files give some assurance over me being a bad sysadmin. That’s either a sweet spot or uncanny valley depending on your perspective. :)
Not that much, given that basic accounts are free. I guess that in addition to the building from source option, self-hosted Bitwarden (or at least Bitwarden-rs) includes all enterprise features for free.
The two most useful ones are probably sharing selected passwords with other users / groups, and attaching encrypted files to logins.
I wouldn't bother setting up a server and domain solely for it, but if you already have a personal webserver with a reliable backup strategy, since Bitwarden_rs barely uses any resources and is super easy to install, you might as well throw it in.
That's my case - I was already running a personal Nextcloud and Fediverse instance, so adding Bitwarden was like five lines of docker-compose and four of Caddyfile.
It also doesn't have to be exposed to the internet. You can have it accessible behind wireguard for instance.
I have it, a DNS server, cloud storage, etc on my home lan, and use wireguard to access it on the go.
Personally, I'd trust one of my servers far more than a client shouting "yo someone send me a file to overwrite my db with" over multicast on the local starbucks wifi...
I have the exact opposite feeling. I would not selfhost email but I would selfhost a password manager and my files behind WireGuard, like many have said.
I have almost moved from cloud hosting to home server. This perfectly reasonable for non critical services that don’t require more than 90% availability. The simplicity of such a setup nowadays is a breeze of fresh air. Debian stable, WireGuard, syncthing, ssh, git, ... all are low maintenance and works fine with Linux and iOS clients.
Note that I use syncthing for the casual read only "important documents", such as ID copies, tax documents, ebooks, etc. I don’t sync photos, movies and such. Most editable documents are in git repos.
I sometimes work on my iPad, and then I use a ssh client or the ish app (a shell, with vim, etc).
I have used this setup for years, and it’s just low friction, low maintenance for me. I have thought about using an own cloud/nextcloud setup, but it’s just too much work for little value. Like running gitlab instead of ssh and git.
If you mean they may have a vulnerability, they've gone through a few security audits.
If you mean you can't adequately keep your own server secure, then pass it.
1password used to have a peer to peer sync mode that I loved. No need for a server anywhere. You would open it on your Mac and then open it on your phone and if they were on the same network they would self discover. Too inconvenient, perhaps, for most users, but for the paranoid like me, it was ideal -- no servers involved at all.
(Technically, wifi sync I believe still exists IF you use 1password on Mac with a old style local vault, but it's basically unsupported. Mine just stopped working and I switched to 1password.com.)