I've recently seen other people make similar posts complaining about how it feels to play the jungle role. I will attempt to throw in my perspective and please comment your thoughts on it.
Its been changed in all the wrong ways and has become dependent on how knowledgeable in warding people are to either invalidate a role or be dominated by it. Warding however was made into an expensive luxury you couldn't afford in the early game so laners and junglers can't defend as easily from ganks and invades making the pressure potential for junglers in the early game the strongest out of any other role at any time.
Getting lvl 3 was made even harder. It's risky to go a champ that has to do 4 camps or the krug route to be made relevant if the opposing jungler can just do double buffs then perma gank 2 lanes in the meanwhile, gaining tempo.
Heaven forbid if as a jungler you get invaded and 2 of your camps stolen, you are S.O.L. and you and your team are now on a slippery slope to defeat as you get more choked for resources if the enemy doesn't throw their tempo advantage.
All/Some of this CAN be attributed to (but most likely not) Riot wanting pro play not be 25 minutes snooze fest of people farming/warding/ward clearing then having 1-2 lackluster team fights.
As of right now the jungle role is 100% dependent on how competent your team is, insomuch as how much they can exploit the tempo and value you create. The jungle is a power multiplier for you team, and if your team is 0 doesn't really matter how strong you are. Same is true if you have a jungler that doesn't know what they're doing or got screwed. If they do bad generally the whole team will suffer because of the inability to secure game-winning objectives.
TLDR: Jungle has been slowly strangled in what options they have to get/maintain/catch-up in tempo and people are tired of it.