(on why STJs aren't as detached as NTJs)
My theory is that it's because STJs often find themselves more invested in the details of things than NTJs do. I've seen the Ni vs. Si difference with regard to those two sets of types as a matter of strategy vs. tactics. STJs, considering their natural tactical abilities, find themselves much more involved in details, on the ground level. NTJs, on the other hand, handle the general strategy, without needing to get quite so immersed in the entire enterprise. Both STJs and NTJs are frustrated by things being done wrong, and may be offended by things being done wrong, but when STJs are so much more invested in the details, they naturally see a lot more that's wrong with everything on a daily basis, and are required, in a sense, to invest themselves in it -- with that investment being, among other things, an emotional one. So if ESTJs have more of a reputation for this sort of hair-trigger offendedness than their introverted cousins, it's because being Te-dominant makes them more likely to barge into things and try to fix them when they're broken -- meaning, even more situations come up on a regular basis that would make them invested in issues, emotionally tied to their inevitable success or failure, etc.