Hope it's okay that I just reply to everyone

Wiggling is down to lack of precision and lack of subpixel rendering, unrelated to Z buffering. Z buffers are for hidden surface removal, if you see wiggling on a single triangle floating in a void, it's not a Z buffer problem.

When you see models clipping through themselves because the triangles can't hide each other, that's the lack of Z buffer.

Thanks for clarifying. I knew I was getting something wrong, but can never remember all the details. IIRC PS1 also suffered from render order issues that required some workarounds, problems the N64 and later consoles didn't have.

The lack of media storage was thing that kind of solidified a lot of those issue. Many that worked on the N64 have said that the texture cache on the system was fine enough for the time. Not great but not terrible. The issue was that you were working in 8MB or 16MB space for the entire game. 32MB carts where rare and less than a dozen ever used 64MB carts.