This is a little bit off-topic (but just a little).
IMHO, this user verification requirement for passkeys stored on a password manager makes no sense at all.
UV is required for physical keys to prevent the use of a credential by someone that found a key that is not his. Making it truly MFA, the key is something you have and the pin (or biometric verification) is something you know (or something you are).
And there it does make all the sense in the world.
But not for passkeys stored on a password manager, I already verified myself when i logged in (or unlocked) it.
I really see no need at all to require an additional verification every friking time I use a passkey stored on my password manager.
And if this makes any password manager passkeys implementation non-compliant with the fido specifications, then those specifications should be changed.
Bitwarden, as a member of the FIDO Alliance, should (again, IMHO) push for that change.
The way this is implemented right now in Bitwarden, it is going to slow down passkeys adoption by users (more than one person in this thread already expressed this sentiment, which I share).
Or worse: it is going to make users weaken their vault unlock pins.
And all, (again, for the third time, IMHO) for no gain at all in security (which is the worst part).