Very true.
Years ago, it seemed to me that given the speed of the game, it was remarkable how generally accurate the officiating usually was. I'm not suggesting that there weren't biased calls here and there, but that the refs seemed to get things right the vast majority of the time.
I have no empirical data to back this up, but it seems like things took a turn for the worse with the advent of replay. You'd think that this would make things more accurate, but it seems like not only do refs get things wrong more often, but they often make snap calls as if expecting to fall back on calls being challenged and / or prospectively overturned on replay.
Again, that is not data driven -- just my opinion -- but it seems like refs are an order of magnitude less on point than they used to be before they had all of these fallback options.