The short answer
Average RevOps answers questions. Top decile RevOps changes decisions. Concretely, the difference shows up in four places: they publish a small number of definitions and defend them, so the company stops arguing about what a qualified opportunity is; they own the planning model (capacity, quota, pipeline required) rather than just reporting on it after the fact; they instrument new motions before launch instead of retrofitting tracking three months in; and they say no to tools and fields, which is the least popular and highest leverage thing they do. The tell is simple. If the weekly forecast call spends its time debating whether the numbers are right, ops is average. If it spends its time debating what to do about the numbers, ops is doing its job.