system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do older emulated games still occasionally slow down when rendering too many sprites, even though it's running on hardware thousands of times faster than what it was programmed on originally?
gpt
A lot of old games are hard-coded to expect a certain processor speed.  The old console had so many updates per second and the software is using that timer to control the speed of the game.

When that software is emulated that causes a problem - modern processors are a hundred times faster and will update (and play) the game 100x faster.

So the emulation community has two options: 

1) completely redo the game code to accept any random update rate from a lightning-fast modern CPU

Or

2) artificiality limit the core emulation software to the original update speed of the console

Usually they go with option 2, which preserves the original code but also "preserves" any slowdowns or oddities caused by the limited resources of the original hardware.