Who thought this was even a good idea?
Let's think about it:
You have a role that is designed to not be in a lane. Instead it is designed to get lanes ahead. Ok, that's fine. Create 2 v 1's or 3 v 2's in order to get lanes ahead, rather than just have the game be a display of laning prowess. But this is really, really bad. Like, the idea's fine, but the way it works is not, especially with exp nerfs.
The problem with this role is that, right now especially, there is no way to do anything on your own as a jungler. Tell me, other than camps or dragon/herald, what can you do solo? You are entirely reliant on your laners in order to do anything. This is even worse this season, as, think about this scenario:
You're a jungler. You've hit level 4, and by that time, enemy mid or top is probably 6. Well, you're gonna have a big problem here. Because even if you 2 v 1, there's a pretty good chance they will just focus you and turn the 2 v 1 into a 1 for 1 kill trade.
I know lots of people say that "but jungle is the best role to climb with, you have the most control".
Why doesn't jungle have control over the map? Well, for example, setting up a good gank often requires good gank setup. That often requires laners to understand wave management, how to positon well, when to fight, etc. But low elo-that's not happening. Most of the time, your lanes in low elo will just mindlessly push. Always. Both laners are eternally pushing. Guess what happens if lanes are always pushing? Tower dives. But guess what? It's low elo, so the chances of a good tower dive are pretty low. Sure, maybe you get the kill, but it'll still probably be a 1 for 1.
Prio also plays a part in map control, but again, that doesn't work when lanes are too dumb to recognize what to do. I mean, in my Kindred game, mid had prio and should have responded to me fighting Amumu, as we could have easily won. Did she? No. Because jungle is ultimately entirely reliant on laners.
Is a lane feeding? You can't gank that lane, espeically now that jungle has less exp, a lot of champions dont' have too hard a time 1 v 2ing from ahead. That's out of your control, you can't gank that lane.
Did you make a play that's theoretically good (i.e. vertical jungling when you have prio in mid or the nearest lane)? Well, it might end up costing you because you depend on your laners to do anything.
I know a lot of people will say "but smurfs climb out of low elo all the time playing jungle, it's obviously good at carrying". No, it's not. A player in bronze should have bronze level skills, unlike a smurf in bronze who might have Diamond level skills. Of course the diamond player will climb. But that doesn't mean a bronze player will, because a bronze is matched with players of equal skill. Not only this, but you could say that for literally any role-Bang went to NA and climbed out of Iron (even he lost some games in Iron though). Smurfs will climb no matter the role. Comparing a smurf to a regular player isn't really a valid way to say a role is strong or weak on its own.
I just think jungle is WAY too dependent on laners. Lane feeding? Can't gank. Have prio and make a play? Risk dying if your laners are bad. You can't solo kill anybody, or do anything on your own.