Depth to movement mechanics is one of the differences between mediocre and great first person games. Look at counter strike movement over the years. Players have extracted everything from the quirks of that engine, the game is better for it, and the skill ceiling for movement alone is enormous. That skill ceiling is important. Crouch jumps in particular have been in pretty much every game i can think of since i learned halo on the og xbox. even if they aren’t explicitly used by the game designers, there is often tricks you can do to exploit campaigns in fun ways, or maneuver the multiplayer with a higher level of expertise than others. Thats fun. Competitive but fun.
Compared to games where every mechanic is dead simple and everyone can do it, its more just rock paper scissors at that point. The designer gave a specific movement ability, you counter it with some other ability they designed. Its boring to me.