Why Bitwarden is so bad in placing passwords (autofill)?

That was brought up here (if it’s the same issue you are alluding to):

As far as I understand it, one way Bitwarden monitors autofill is making use of user’s autofill issue reports that come in via the Google forms mentioned before. (the more reports to a site come in, the more likely they’ll prioritize a fix, I guess)

Just FYI, this is a community forum. Your posts may or may not be seen by a Bitwarden employee.