The Prey System is an attempt to add the anxiety of questing on a PvP server, for people who think they don’t like world pvp but also realize that something is missing from their open world experience.
It will fail. The anxiety is the reward. The need to rely on nearby faction mates to defend against an alien “other” taps into our tribal natures in a way that is holistically satisfying. Just like warmode, the ability to turn the prey system on and off is a hidden weakness. Blizzard is counting on the fact that it is PvE, to make it more accessible, but getting ganked by an NPC while trying to complete a quest will be just as annoying, though perhaps less visceral, which is all the more reason to turn it off.