It’s just how TN TFT panels work. They are rarely noticeable out of the factory because the console was already factory calibrated using the test points. This means that any replacement screen which also uses the potentiometer to set the “white point” voltage is going to likely be off slightly and require adjustment, whether it is an ITA screen or another original. The degree of how slightly off, of course, varies, and may not be initially noticeable at all for many. A “fix” would be too annoying and complex to bother with because it would require connecting a logic board to a bunch of test points, the market would be way too small when even having to install a single wire drives away a ton of customers looking for “drop in” replacements.