This is a good thing in my book. I guess you could explain it away with cybernetic augmentation, but still seems like unnecessary hand-holding in a game where stealth is just one alternative.
I don't se how it's handhelding as it's basic GUI aid. Same way as health meter, armor meter, damage location, compass, friend / enemy targeting color, minimap, item quickslots ect ect.
It was done really well in Splinter Cell Conviction, where if you were hidden in the shadows enough the screen would turn black and white. I'm not saying this effect is a good idea in Deus Ex, but there are ways to tell the player he's hidden enough with simple screen effects.