depends on what kind of ips panel you're talking about. 8bit and 10bit panels have far greater color accuracy - that combined with their wide viewing angle makes them superior in some cases. the el cheapo 6bit panels have no such advantage except wider viewing angles. tn panels can have an advantage if 120/144hz however they are much worse in terms of viewing angle which can be quite noticeable on larger screens as the corners could start to color shift.
at best both do have their own advantages - at worst they are equal.