I think the traditional way to do that is via dm-crypt, which you can set up with an ssh server.

You can also use a network-shared file rather than a password for LUKS but it’s not as straightforward to set up as a password. If you are doing something like tailscale then it’d be unlocked as long as you are on the VPN

Typing in a password in-person at a data center would be a huge hassle, agreed