The PSX was literally known for Crash Bandicoot right out the gates. It was one of the biggest titles on the system. The N64 is only known for 3D platforming because it has so few quality games that Mario 64 stands out among them. You can debate the quality of Rare games, most of them aren't very good and only hold up on nostalgia.
Comparing Spyro to Mario 64 is insulting to Mario 64. Spyro does very little with it's enviroments that come even close to a Mario 64 level.
>PSX has 2D stuff
Very little of it compared to 3D stuff.
You keep moving the goal posts for what you think counts as a 3D platformer. You seem to define it as only an open world (as was possible at the time) platformer. But that doesn't stop Crash being 3D.