Do you know why the average pf player is so bad?

[Lyth]

I don't think that any of these fights are designed to be mechanically difficult from a reaction time/finemotor precision perspective. You're generally solving a series of movement puzzles. Fights start with a mechanics showcase where they teach you the 'vocabulary' for that fight. The latter part of the fight involves you applying that 'vocabulary' to progressively more elaborate mechanic strings in order to find the safe spot. That's also why a lot of recurring mechanics (Stack/Spread/Protean/Shakers/Chariot/Dynamo/TB) have very standardized signposting so that they don't have to waste too much time reteaching those things individually. Harder fights just tend to give you longer mechanic strings, less time to resolve the safe spot, and have a longer duration.

This also means that having completed more content will help you learn subsequent fights a lot faster. The reason why there are some significant skill gaps between players is because some people have been playing across many years and have seen a lot of these patterns many times before, while others are completely fresh. There's also a degree of fear around moving up into harder content types, in part because seeing multiple mechanics intersect at the same time can be daunting when you first see it. But when you actually make that jump and clear a harder fight, everything pitched at the previous difficulty seems trivial, to the point that you can't remember how it ever challenged you in the first place. I think you can teach most people how to do the content in this game with some guidance and patience, but there definitely are some barriers built into progression that prevent people from doing so.