As far as a desktop app, it's electron-based, but there is a cross-platform Bitwarden app that seems to work well enough (responsive, minimizes to tray, etc).
I've yet to import all my passwords into Bitwarden (still comparing the Ruby, Go, and Rust standalone server implementations), so I guess we'll see where the experience is after I fully switch.
Regarding 2FA, while it doesn't totally expose you, if you put your token in your PW manager, you've definitely significantly weakened your security.
..and it works great. Same as 1Password X for Chrome, it does not require a desktop app, and handles certain things like TOTP a bit more seamlessly.