I guess this is tangentially related. RDR2 had the full ending for Author and then kept going. I didn't care what happened beyond that so I never finished the epilogue.

Ys 8 has a soft lock toward the end where if you didn't do enough side quests to build up enough affinity with your castaway group and party members you would get treated to a bad/neutral ending. Fortunately at that soft lock point there are enough ways to build up those points so you can progress past that point.

Little Big Adventure 2. Just before the last boss I managed to save myself on the last island without a way to leave it. But I needed to leave and get another Ball or w/e it was to unluck a door. It was my first real pc game experience ever. Dunno why I stuck with this hobby after that tbh :)

I can't remember the exact method, and I may even be remembering the wrong game, but I think in Breath of Fire 1 there was an item that you needed that could be sold, or maybe not picked up, and if you didn't have it, you'd get locked out of a puzzle much later in the game. It was hard to fuck up, but if you did, it was 30 hours of game down the drain.

King Kong for the PS2 had a fire puzzle, where if you dropped the torch in the last section, you couldn't get a new source of fire. So you were stuck at a section where you had to burn away wood in the path forwards, but couldn't go backwards to get the fire.

this one reminds me of Farcry 4. The one with Pagan Min.

if you just stay and be a good boy, you get a free trip to where you really wanted to go.

It's easy to not do this because maybe the welcoming committee is not around anybody's standards.

The Ooze. My memory on this is fuzzy but on genetics lab part 2, there is a room you can enter that has a checkpoint. If you enter the room then you're locked inside and if you collect the checkpoint and die, you will respawn back into the room and your only option is to lose all your lives or reset the game. I remember getting really pissed off finding this when I was a kid because I spent days trying to beat the game and I had a really good run up until that moment.