The team can invalidate the jungler faster than EXP deficits.
I want to say the exp nerfs have inhibited the ways that you can play as a jungler but the game quickly becomes impossible to play if 1 or 2 more of your lanes feed or can't maintain priority. You can't go for scuttle crabs cause the winning midlaner will just rotate and kill you. You can't sneak dragons because the fed bot lane will rotate and kill you while your laners stay in lane and farm. I know this has always been true to some extent but it's been heavily exacerbated by recent jungle changes.
If a lane feeds and becomes impossible to gank, especially mid lane or bot lane, parts of the map that matter most become restricted before you can really affect the game. And on top of all of this you will be 2 to 3 levels behind and getting pinged that you're alive because someone gave up 2 or more deaths before the 6 minute mark. Before you know it, the enemy team nearly has the dragon soul win condition captured all because one person feeding flipped the game upside down. It feels like jungling has absolutely no room for error now.
I was watching a TF Blade video of him carrying a top lane game yesterday. He smurfing in platinum but the enemy laner had given up 6 kills by the 8 minute mark. TF Blade is already level 9 and the enemy jungler is level 5, with a tier 2 tower already halfway dead. What the hell do you do as a jungler in this situation? What CAN you do?