[saturn8601]

I don't think the PSX has enough ram to allow large open world and near instant movement from one open world to another. Yes there were things like streaming in textures like Spyro did but if you watch footage of Zelda 64 in the big open worlds I just can't see it being done that way on the PSX. Even spyro had long load times between worlds. There was a lot of innovation on the PSX in terms of genres but little to no major open world games.

[cubefox]

It's not a real open world game anyway. It consists of various connected areas. Open world would be something like Driver, which was indeed a PS1 game.