What is Kennen's weakness?

So far as I can tell, he has every base covered and there's no real downside to him or ways to beat him. He's got a strong laning phase due to being ranged, good auto attacks, high base damage, and not needing to manage mana. He can't really be bullied due to his range and using energy along with a solid poke ability, but he can easily blow his opponent apart the instant he hits 6 with nothing but . He's got both burst and some solid sustained damage due to having empowered autos. His E gives him high mobility and built in durability to make him hard to kill, chase, escape, or really interact with in any way that doesn't end with him winning. His damage is pretty much entirely unavoidable with Q being the only thing that isnt targeted or a large aoe. His Ws let him instantly apply 2 out of the 3 stacks necessary for his stun and both stacks are targeted so he can W-W then E in for the stun and oneshot you whenever his R is off cd. There's no limit to how frequently he can stun the same target, although it does get a reduced duration if reapplied too quickly so there's that. His cds are all fairly low, even his ult. He has good ratios too so he scales up rather than falling off, and despite being mobile, spammy, and having a shitload of damage, he has more cc than most tanks, with his ult being an objectively better version of 's ult.

So I'm genuinely asking... what beats Kennen? What weakness does he have?