It drops you before this point so you could see all the endings on the same save. In games like masseffect 2 or witcher 3 the ending was everytime the same with some smaller parts changed (in witcher 3 it was the epilogue and in mass effect some people may die or not die during the suicide mission). You could decide who dies in me2 by doing sidequests but if u did every sidequest then theoretically nobody dies so where's the point of playing it again, to make somebody die you would have to make the new save and don't complete some of the quests. In cp2077 making sidequests only allows you to choose different ending. Every ending is something else, we have 4 last missions that are completely different and took about 1,5h to complete each so it makes about 6h if u wanna do every last mission in the game . They put you back to point of no return so you could see them all.
Final Fantasy XV also dropped you off before the "point of no return" post game, actually "post game" is basically talking to his dog and having him reliving the memory of being in Lucious.
In one of their DLC they added a "versus" ending which is far happier, where Noctis doesn't die, and they found a way to get rid of the Starscourge for good, and he became king to rule in the land. I think big part of it was players complaining how much the ending of FFXV sucked. But the damage was done and they canceled like 3 or 4 DLC that they had planned which would have significantly expanded the lore and story.
That game, like Cyberpunk 2077 had much shorter main story (you could quick dash them in 6 hours basically) but a lot, I mean a lot of side quests. But most of that was filler fetch quests.