The reason there's so many Lee Sin QQ threads is because apparently out of all the 120+ champions in League he's the only one that can have an atrociously high amount of people who think he's a serious problem, have Riot state several times over several years that he's a problem, and be a top (if not outright dominant) pick in a role for 3+ years without so much as a lovetap to his power.
Riot has outright said (as in, "you can google that shit and read it for yourself") Lee Sin has too much crap and versatility in his kit, as well as saying that, regardless of what larger-scale jungle changes they make, Lee Sin is always at-or-near the top of jungler list in levels of power. They have said these same things several times over a 3+ year long period, and yet still refuse to change the champion, purely because of his disgustingly high play rate and the fact that his flashy kit looks like "outplaying" to idiots who don't know what his kit does.
There's a shitload of Lee Sin QQ threads, because JUNGLERS ARE TIRED OF HIM GETTING A FREE RIDE IN THIS GAME. We're tired of him being obviously having a kit that's way too overloaded, obviously being a major issue for the jungle state, and obviously crowding out jungle picks, yet never seeing any real work while every other champion in the role has to sit through both painful jungle nerfs and equally painful specific champion nerfs.
Sure, you can say "he's not that bad". But frankly, unless you're a jungle main who isn't a Lee Sin main, I'm sorry but there's no other way to say it besides "you don't have a goddamn clue what you're talking about". It's a jungler problem, it's long been a jungler problem, and it's a problem Riot ignores purely out of favoritism for a horrendous champion design.
If you're playing a lot of Lux, I'll throw out of a random guess and say you're a mid laner, so consider this: Lee Sin is to junglers what Kassadin was (pre-rework) to mid laners. He's an incredibly outdated kit design, with a downright stupid amount of options, that can stomp you in your role simply because the other guy can find his QWER keys, who Riot refuses to acknowledge simply because they like how he looks. The difference is, Riot's opinion on Kassadin was that "he probably shouldn't be an assassin, his ult's too strong", and they eventually did some work on him. Riot's opinion on Lee Sin however is "we know and will publicly state he's too strong and definitely way too overloaded, but frankly we don't give enough of a fuck about jungle players to do anything about it".
That's why there's an assload of "Lee Sin QQ threads": Because jungle mains are sick of this bullshit, and having more and more terrible global jungle changes happen to "add diversity" while they completely ignore the single largest stranglehold in the game on "jungler diversity", who we've been saying for years needs to get changed, is a slap in the face.