Tryndamere is broken AF?

So just want some input here and some advice if any high elo players end up reading this.

Basically here is my scenario: I'm plat player and don't see many tryndamere's often. He's like yorik, poppy or urgot or one of those other champs you don't see very often. But every time I do see one, the team has to completely camp the crap out of that lane all game (if he's jungle as in the last game I played that's not possible) or if he gets a kill its GG for my team.

Why? Because If he gets even 2 or 3 kills he can 3 hit auto you to death. Which is what happened when I was playing khazix recently. If you try to kill him, his ult lasts for eons and its nearly impossible to do so (yes I know that you pop an ignite on him near the end of the ult and it works sometimes but not all the time). If he gets even more fed than that he can quite literally 1v5 the team.

What if he doesn't get fed? Well then friends he is able to split push better than anyone else in the game bar none. He has a slow, a spin that has low cooldown (and that can get him over walls as well?). He's ad/crit so he takes turrets fast AF and you can't catch him when he does this.

FOR TLDR: So... Why is a hyper carry given an invincibility that lasts for eons, can 3 shot nearly anyone when fed, and have incredibly high mobility? This is broken?