As a life long hunter, I stalk my prey, but their senses are very keen. Even moving upwind on quiet ground and masking scent I am never 100% successful, and not even close. Investing in stealth would give you an advantage on unwary prey, but it sounds like some folks here are looking for certainty. An alerted adversary is impossible to surprise.
Game theory in a complex multiplayer game involves scenarios that require skill diversity. In the "simplicated" metaphor, there are multiple ways to clear a room. Good POI design would bring all the play styles some love, but not in every room. If I'm a H2H strength build, I will occasionally face feral irradiated tough opponent. I don't get the x9 times damage bonus verses bikers perk. Maybe the smart move is to let the stealthy player take out the biker. But, in the next room they are alerted, so the intellect build with turrets or tank with a club gets the love while the stealth player participates.
Balancing PVE and PVP in a game like this is tough. You don't want to over or under advantage one play style or everyone chooses the exact same build.