In most of the world, it’s something like 200-400 people per bus stop in a city. In the US, you’re lucky to see 1200 outside of a few edge cases.

Hmm I couldn’t reproduce this, which places did you check? I’ve checked most of the larger cities in Europe and the US. They all seem to have similar numbers, around 800-1000 people per bus stop.

I’ve also noticed that larger population densities usually have less bus stops per population. Which makes sense, as rural areas tend to rely more on buses because they don’t have access to trams or subways. Plus, for higher population densities you need less stops per population, because doubling the amount of bus stops only reduces walk times to the nearest stop by 30%, assuming an equal spread (Circle Area = Pi * Radius²).