I would pick the same #1 as you as well. Given a random NFL team against random NFL opponents with 2 minutes left on the clock and down by 6. If your time machine could pick any of the QB’s mentioned at their prime.........who WOULDN’T pick Joe Montana?
I’m not a Niners fan but I grew up and worked as a teenager a few miles from Sierra College, where they had summer camp in the Bill Walsh era. I still have the autographs of Walsh, Chuck Studley and Ronnie Lott on a menu. :)