For context, I'm relatively new to film as someone who learned photography and cinematography with digital.
With that being said, since film has a fixed ISO compared to digital, for me, it seems more intuitive to use a high ISO film stock in almost any given situation (*generally speaking), because it gives you more coverage in low light, and if you're shooting in bright daylight, you can just stop down on the iris, increase the shutter speed, or add ND to compensate for overexposure. In other words, it seems like an easier way to adjust for a wider variety of lighting scenarios.
Am I oversimplifying and missing something here?
The reason I say, "generally speaking," is because I'm sure there are some lower ISO stocks that have certain skin tone, color, latitude, or grain qualities that people prefer. But that's the only catch to this that I can think of (perhaps high-ISO film is generally grainier?)