I often think that to myself as well to be honest. Originally, it was mostly because it's the only "secure" system that I'm currently hosting and I wanted the ability to airgap it without taking the rest of my homelab offline.

I mostly use my homelab for tinkering/applying what I'm learning without breaking a production system at work so needless to say I've learned a lot since I originally deployed bitwarden... Now it's just because I'm too lazy to spin a new vm and migrate everything.