And yeah, GGG has always had issues with risk-reward type stuff. I talked about this with Echelon the other day - stuff like Warbands (the big ones) or Invasion bosses are great concepts in general. Stronger specific mobs that force you to slow down/and or engage them? Great!
...until they drop jack shit and the choice is between cruising past them and leaving them in the dust or risk a potentially dangerous engagement for no real gain and a time loss.
In my ideal PoE world drops (and maybe even XP) would be based off of how many players skip/do certain content. Xandro should drop better loot than other exiles, Hailrake or Abaxoth should drop more than Strangledrift (and yes I had to actually look up that name). Apart from that kind of fantasy at least something like rewards being tuned around TTK would be something.
Mayyybe the XP/h rework for maps is the start to something like that but I'm not very hopeful. This is an entirely different topic though. Without introducing some kind of upper limit on player damage something like this would just widen the gap between builds.