A few minor corrections there mate.....
The Bills actually lost four consecutive Super Bowls.
The final score was 15-13. Giants kicked 5 field goals, the last of them as time expired to deny the 49ers their shot at a threepeat.
It wasn't LT who nailed Montana, it was Leonard Marshall.
Montana was about to get tackled by LT, but side stepped him.
Unfortunately for him, that sidestep put him right in Marshall's path of pursuit and Marshall HIT THE BULLSEYE, right between the shoulder blades. A BRUTAL HIT. Watching it live, the delay felt like a lifetime.
When Montana finally got up and limped gingerly to the sidelines, he had the look of someone who had been flattened by a Sumo wrestler. He had his bell well and truly rung. Probably thought it was Wednesday and his surname was Vermont.
There was actually a little bit of a story behind that hit....
I once watched an episode of America's Game, a series about the 20 greatest Super Bowl Champions.
The 1990 NY Giants were one of those 20 teams. It featured Jeff Hostetler (the backup QB you spoke of), running back Otis Anderson and linebacker Carl Davis (a very underrated member of that awesome Giants defense of the 80s. I mean they were LOADED throughout the decade. Marshall, Davis, LT, Harry Carson, George Martin, Pepper Johnson, Steve DeOssie, Erik Howard, Jim Burt and Gary Reasons (going to include a vid of him that is a personal favourite).
Davis alluded to that hit being an act of retribution when Burt (whose number 64 on his jersey would stretch like fuck due to the insane amount of pads back then

) landed on Hostetler's leg, temporarily putting him out of the game.*
That made the Giants defense proper angry, because it was their former teammate who did it and they thought it was deliberate.
* how he managed to actually recover, return to the game and lead them down the field for the winning field goal, I will never know.
Fast forward to 28 minutes 55 seconds of the video below....
I don't know if you have ever watched any of the America's Game episodes mack, but if you haven't, then
find some time to watch them. They are well worth spending time on. NFL Films know how to make great content.
Ironically, Jim Burt, when he was with the Giants, himself knocked Montana out of a playoff game in the 1986 playoffs. So he has direct involvement and indirect involvement in Montana getting taken out of a playoff game. Joe Cool must love him lol.
Everything else you said, I could not wholeheartedly agree more with.
And now that Gary Reasons vid. With the legendary Summerall and Madden in the booth. Good times