The main difference for me is if you want to use it on multiple devices, for example your computer and your phone.

In bitwarden this is seamless because it always saves to the cloud. With keepass you have to manually set up the file sharing with syncthing/dropbox/etc. One problem I had is that sometimes the file sync I set up wouldn't work properly and I'd add new passwords on the phone before it received the latest file version from the computer. When that happens you end up with some passwords that are only on the computer and some that are only on the phone, which is something that syncthing can't fix by itself.