You got people commenting on here and you're still asking why downvotes, are you really that clueless? You literally listed what traits kled has, I can do the same for any other champion and make it sound op. Truth is kled isn't as op as you make him out to be, which is why you're getting downvoted because you claimed he was op and provided weak evidence of it.
I'll provide some weaknesses for you since you can't:
"tankiest in the game for free"- no he's not the tankiest he gets litttle to no resistances, its just purely hp that goes away once you get him low enough. He's as good as dead if you damage him enough for skarrl to run off.
"invulnerability" - Yes, and fizz and vlad have invulnerability as well must be too op.
"Global Dash" - ? It's not a global dash whatsoever its a speed up, not a dash there's a big difference there.
"Not one but two huge range dashes" - The dashes are tiny and they can't even go over walls. He only gets 1 if he hits nothing and if he hits something he can only choose to dash back through it.
"Mini Thresh Chain" - The chain range is tiny and break off range is even tinier.
"Easy to 1 shot people" - Not sure where you're getting this from but I haven't even gotten threatened by a Kled in my games yet. He does little to no damage to me.
He can be kited super easily and he's similar to a leona. He all-ins with his 4 hit passive and q and double dash. He can't selectively choose to disengage like a renekton after trading.
He does little damage by himself late game. Needs his carries to do damage, thats enough of a weakness that he can't solo carry.