Don’t know much about the old heads but from my understanding young was deemed a bust just happy to take any job. And then luckily Montana was out for two seasons.
Walsh traded for Young in 87’ because he was worried about Montana’s health, and figured he could mold the talented but unpolished Young into a great QB. Young was definitely considered a disappointment in the USFL and TB after being so highly sought after at BYU.
Montana had a career threatening back injury in 86’, and then got knocked unconscious by Jim Burt in the playoff game. Montana was a skinny guy, and there were always some questions on how long he would last.
Montana had a great 87’ regular season but stunk it up in the playoffs and got replaced by Young. So Walsh spent much of 88’ going back and forth between Montana and Young before finally going with Joe, and then Joe led them to 2 more SBs
Walsh apparently said (lied) to Young that he’d be starting by his 2nd season in SF. Young didn’t start until his 5th season, and that was only because Montana messed up his elbow. And in that season, the Niners had more success with Steve Bono than Steve Young. Jerry Rice would publicly say he liked Bono better because Young ran around too much.