In a nutshell,
i.e. programmers and real people perceive "contrast" in a different way - selecting "increase contrast" should make things better for the average Joe, actually it f up things.
Only trouble is that that "Accessibility" is a System Preference and the reduced transparency is very good for my old eyes in most situations. So I have to screw up everything else to accommodate FMP? Sad!
Completely yours on that.