Why are the Mario Kart 64 Computers so Fast? [video]

Interesting.

Half the differences feel like optimizations, and the other half like game design.

And then you have the bugs. If you fall behind the slow computer players they travel at top speed forever and you can't win. That's either a bug, or it's intended to make losing feel more like losing just like winning feels more like a close contest, but I don't think games are designed to make losers feel like losers. They're supposed to be biased towards humans winning while feeling like there's real competition.

If you wrote a new racing game today from scratch you might not think about these things. Like keeping the same characters having the same relative skill levels throughout the tournament. You might not think of that and make all AI characters behave the same and they will feel less real.