Nobody likes RNG. People like progression. If you ever went hunting for glams on dungeons unsync you know how hell it is to spend 4 hours doing the same thing over and over again and waiting for the one piece of glam to drop while you keep losing braincells. Grinding is supposed to be fun and chill and not damaging to your brain. Can you imagine if instead of PVP rankings we had "if you win, you have a chance to climb"? We have examples of good RNG systems in the game already, Wondrous Tails is a good one. Yeah, it's RNG af but I can spend points to try again, and if I keep playing I can refill these points. All I need is the feeling that I'm not totally dependent on RNG.

For dungeons specifically, it would be much better if whenever you have a specific type of gear, it wouldn't drop on chests. And no, you don't need to clear the last boss for that (most of the glam huntings will be unsync after all). It's still RNG but it's limited, and even if I don't get my item straight away, I will feel that I'm working towards a goal.