Most players are smart enough to bring a throwaway character with no xp on it to bosses already, and they still just stand here, and this would change nothing. It's simply not worth the effort to activelly hit the bosses. PA could easily solve this issue if dps would actually matter on the loot.

I believe there are dmg brackets that are connected to loot increase already. Isnt that the case? If not, I might leave my tuvala alts with 0xp stand there as well lol.

There are brackets true, the problem is that the extra rewards are so low that it doesn't worth the effort.

The goal of PA is not for you to play and have fun, it's for you to be connected and spend monies ;)
Once you know that... either you bring main that will not be one shot. Or you punch and wait. Anyway, loot is rng... i get better loot with just a punch than fighting for 20mins. So join boss discord, connect last min, hit, enjoy and back to your afk fishing :D

There are games where you can even lose a lvl as soon exp falls below 0. Thats not the case in bdo.

But as ASM has written, removing it on worldbosses would be a great thing.

Some people want the game to be too much friendly, and that's the one of the many reasons that WoW is slowly dying (maintaining a lot of players still, yes). Introduction of karma system, marni realm, guild dec changes etc.. Many players quit bdo because of that. Because the game is not dangerous, and not unforgivable anymore. And I can say I'm on both sides tbh, some changes should be done so the game is not annoying to play, but at the same time you don't have that feeling that you can be attacked anytime, anywhere, and/or lose something. At this point let's make also crystals indestructible, not losing xp anywhere, and perma 24/7 marni realm. And the game will be boring as never before, also players will be disconnected from each other. BDO became more single player than used to be already. I agree with not losing xp on world bosses (and crystals), but not while grinding.