Virtually every game I've won or lost has been dictated by how effective my jungler was.
Laners just don't have the agency, to carry the game anymore, except bot. Mid might if they are a mobile assassin as they can prey on mages and hopefully snowball the game, but in the presence of a decent jungler that's virtually impossible. Lee, Vi, Sej, Zac, etc. There's so much CC in the game right now (with virtually no tradeoff as those champions with that amount of CC are never penalized in damage, sustain, and rarely mobility) that if a jungle decides to camp you, you're fucked. Not farming isn't an option, and for many champions not pushing the lane isn't an option either.
Junglers have the ability to sit in brush for minutes at a time in order to apply immense pressure, and because of the way the jg monsters spawn and catchup exp, it doesn't matter if they fall a little behind in exp (which is hard to do).
Stop making jungle so powerful that it solely determines who wins.
and All these assassins