There's a learning curve for every console on the development side. There are some early NES games which, I'm pretty sure, look like Atari games where the devs got drunk on colors (Kung-Fu?). There are early SNES and GBA games where developers went crazy with Mode 7 because they could (Sonic Advance?). I'm just more sensitive to the PS1/N64-era games because I was properly into the gaming scene then. And yes, even at the time I realized developers were cranking out "3D" because it was the new hotness, and that games built/marketed on graphics would look like crap in a few years. There are certainly late-era PS1 titles that look decent- things were coming together by FFIX and Legend of Dragoon- and some where the graphics were intentionally kept simple enough to age decently (MM Legends).
Still, this brings up an interesting point I noticed- PS1 was, on balance, all about the textures. It could do 2D games like 2D, and most 3D games had high texture content. N64 was all about models and 3D. Textures were fewer and simpler, and I actually think the 3D games aged better, but I can't think of a single 2D N64 title, whereas most 2D PS1 titles have aged great.