FWIW I've been part of it at two public companies as well, and my experience nicely lines up with yours.

Incredibly vague mandates that result in extremely complex rules and systems. Lots of things being marked as "financially sensitive" even though they weren't at all - because better safe than sorry.

In both instances it quite literally cost the company several employees who were assigned to put the SOX systems in place, because it was so incredibly frustrating (and, well, boring), that they ended up quitting down the road and directly attributing their leaving to SOX compliance.