I use KeepassDX on family mobiles with Syncthing for copies between laptop and phones. What would i gain moving to Vaultwarden, knowing that i would never open my network to the outside world? It would be easier to manage for sure, as im having to setup phones and laotops myself in the family and worry that they do silly things like turn off syncthing. But what about offline access to passwords? Does Bitwarden mobile client keep a local copy of database until it can sync?
Do you worry about the sus new maintainer for syncthing-fork on android?
The other maintainer, nel0x (who does the Play Store releases), has started distributing a degoogled version of their own. nel0x is arguably more trustworthy.
If you do don’t trust em then don’t update syncthing - it’ll work for quite a while I assume.
And in addition the keepass safe default encryption of AES-256 and is even secure against theoretically existing quantum computer attacks to our current knowledge. It is designed to be not trusted by the storage owner :)