Really not giving experience much credit, having decades of experience against people with comparable stats and being no worse for wear is actually quite a skill feat. As for Taker's skill, I'm not certain where it lies, aside from the fact that the best pro wrestlers in general are skilled as all hell at acrobatics and all the other intense athletic aspects that go into their performances
Also, Stronghold's listed as "at least High 7-C", so evidently he upscales quite a sizable amount from 160kt, likely meaning the AP gap between him and Taker is less than 3x, maybe even less than 2x