Nah, I'm not saying that you're wrong by any means, pal. And I also understand what you said.
Most developers use shaders and effects to emulate the PSX look, regardless of how the original models look.
I'm not an expert, but I also have some PSX and retro effects that I have bought, and they can make anything look pixelated, even if it was originally high res.
However, if the polygon count is too high, then you will still notice it, even if it's pixelated.
But that's ok to certain degree, because not every PSX style game needs to be 100% faithful to how the games actually looked and played back then.
If we really wanted to make a game that was completely like the original PlayStation, then we wouldn't even have a mouse, let alone 4k, widescreen, and 60fps.