Again, what I see is Friedman and Simpson asking for fairly specific and concrete things, and those things not being provided. More to the point, what I asked

Again, what I see is Friedman and Simpson asking for fairly specific and concrete things, and those things not being provided. More to the point, what I asked for in my previous comment has also not been provided! What does the knowledge that Sets are "just 0-categories" buy me in concrete terms? Does it facilitate the proof of any theorems in set theory?