@zeb, I have never used 1password, so I have no knowledge of if the two products are supposed to behave the same.
Bitwarden does offer to save logins. Please make sure that these settings are checked and that the site in question is not in your “excluded domains”.
The reason I use the so-called kludge is that it is reliable. The “offer to save” occurs after you have created the account on the web site. If something goes wrong, you only become aware of the problem after it would have been easy to make a course-correction.