Absolute utter disgusting stealth mechanics

[Spada]

I have never ever seen a more unfair, ridiculously hard stealth mechanics like in this game.
You crouch walk in the absolute dark to the point where you can't see sh** 2 feet in front of you but it doesn't matter because the AI sees and spots you wonderfully they can see you crouch walk behind objects such as walls and vehicles, of course no biggy it seems the radiation gave them superpowers such as X-Ray vision.
You use a Silencer for your pistol to stealth kill but then of course they know your position afterward. Why use a silencer afterall in this game?
I have never seen a game where the AI exactly knew your location after using a silencer; that's the whole point of using one so you can stealth...
They always move in groups, so even if you somehow manage to take one out, his friend immediately attacks you. What is this?
Like i been stuck at the main quest fabric area after the calm zone for an hour now.

[Baron01]

Stealth is far from ideal but you can actually stealth a bit. I was able to complete certain parts of main mission that required stealth as optional solution. I was able to visit Monolith hospital and remain concealed as well as escape Ward custody in Chemical plan without alerting anyone.
Stealth only works in areas with solid cover and darkness, ie. night. Stealth in open terrain even if there seems to be dense vegetation is pointless as enemies can perfectly see you though the vegetation while you struggle to find your attackers.

[Spada]

Nah this just frustrating and i certainly don’t want to quicksave every 10 steps

[Falconek]

Stealth is definitely not in typical modern action rpg style, where you can crouch 5 centimeters behind a guard and somehow he is not aware of you, just because you're crouching.
Enemies can not only see you, but also hear and in some cases smell. They do not magically forget about your existence after few seconds and if one enemy is aware of you, soon all the others will get alarmed too.
As previous poster said, it is close to impssible to sneak on open spaces, but sneaking in buildings, or behind concrete doors is very doable. You just cannot put a bucket on guard's head and hope that he will not see you, because he has a bucket on his head, like in some other games.