Well ....Everyone except organised play players. I can see why it will annoy organised play players. With 5e, if you're going organised play, players will just have to accept that 5e comes with a degree of DM rulings which you wont be able to influence very much... and if that bothers you, or is important to your character, the answer is dont make a PC based around flexible rules such as hiding. Make another character which relies less on DM judgment calls.
But what if I like sneaky PCs?
That's the main issue.
The rules on the iconic and important things should be clear.
In D&D, that's combat actions, weapons, armor, stealth, detection, lighting, spells, and hit points.
As much as I love tracking, tracking is not important in D&D. Neither is crafting or using rope.
But stealth? Rogues, rangers, monks, and bards are sneaky classes and 5e expands it more with backgrounds. Stealth is important. And if you leave stealth rules up to DM, DM A's rulings can weaken many archetypes whereas DM B's could make rogues broken as heck.
"John, before I make a PC. Can I have your interpretation of hiding?"
"Okay everyone, ignore stealth. No rangers or rogues. Jim says once the orc sees you, you can't hide again."