This is emulated as I'm sure the other videos are, but the PS1 back in the day had no way of running anything this crisp, so the emulator is `enhancing` it here. It's not an actual representation of what the game would have looked like.
It doesn't really work right on "normal" PS1s yet, at least when it was making the rounds a few weeks ago, so you need either an emulator or modded/dev PS1 with more RAM to prevent crashes and most people won't have the latter https://www.reddit.com/r/psx/comments/1p45hrm/comment/nqjtdp.... Probably shared a few months to early.
But yeah, on a "real" PS1 it would be blockier due to lower res. The main rendering problems should be the same though.
nah, it's not even configured to use the extra RAM, though there is a compile option for that. seems like the freeze was some sort of bug in the tessellation code, but I'm rewriting that part, so the bug is gone now. it should be working fine on hardware after I publish the changes.