Why is Heimer even allowed to exist in the current state?

Like, that's my honest question. I see him as one of the most anti-fun champions in the entire game. I'd rather play against old Yorick. I'd rather play against old, unnerfed Poppy, against fcking everything: Teemo, Zed, Yasuo, Nunu, Pantheon, [insert any cancerous champion]. You know why? Because at least I can (or could in cases of those already reworked) do anything meaningful against them (well, with exception of Yorick, but it still wouldn't be as miserable because he at least had some mana costs). But Heimerdinger?

Now, if Heimer goes mid lane, there at least exist champs that can do something against him, something like maybe Lux, or Xerath. But, lots of Heimerdingers go into land of melee champions: top lane. And god forbid you meet him there. I'd rather play against anything but him here, even Quinn, even Vayne.

So what's his problem (or rather, your problem if you are against him)? His turrets, this is the huge problem. Yeah, you could say that they have 20 seconds cd, but what prevents him to set up 3 before even minions come while you are waiting for blue to spawn so you can help your jungler? And once you're there, prepare to be pushed into your turret faster than old Morde ever could push. How about trying to destroy them? Good luck, this crap is tanky as hell from the start. It's not like Yorick's or Malza's minions that die after being hitted with one spell, no, these bastards need 2-3 spells to take down. And before you take down one turret, he has another one ready. What you get for even trying to kill one? 5 gold, lost sanity because in the meantime you have to avoid all of his sht rocket and grenades, lost mana if you are mana resource champion. Too bad he doesn't get any penalty for having a turret destroyed, as setting up new one costs him measily 20 mana, and I doubt you can kill 2 turrets in the matter of 20 seconds to make it in any form worth, unless you wanna commit suicide while doing it. And, as I mentioned, you have to avoid all the crap he throws meanwhile at you, and with his mana costs being nearly meaningless, he can throw that sht at you all day.

So, should I don't care about him in any way and just farm outside of his turrets' range? Well, that means either face tanking the whole minnion wave or letting the wave get into tower range. In the first instance, you'll loose your health really fast, in second, you might loose some minions, not to mention your tower is slowly starting to be melted away. Even recalling to base is a problem, as you have to time it perfectly to teleport back before he eats half of your turret.

So why not gank him? No, no, one more time no, it's a complete waste of time, unless your jungler cheeses him just after 1st buff. Even if you manage to kill him, it is not worth it, because he will come back to his duty of pushing the f*ck out of his lane. And if you really wanna camp Heimer lane, then you leave other lanes susceptible for enemy ganks. Not to mention huge risk that even comes from ganking the bastard, especially after he gets level 6. Either you pull it out perfectly or at least one person dies. And even if noone dies, probably both of you will have to back to base, again, wasting time going back to lane/jungle. All of that for what? 300 gold for one person and 150 gold for the other. While Heimer continues to push and enemy jungler uses the time you wasted on ganking Heimer to his team's advantage.

Then, we get to the most scumbaggy, cancerous build this champion can get, as if this champion wasn't cancer enough: ZZ Rot Portal + Banner of Command. This is final fuck you from Heimer to enemy laner. As if his pushing power wasn't strong enough, now you'll never be able to outpush in time, from now on, even if someone who plays against him didn't die a single time, that player will loose a tower, or even two. If you let Heimer stay at lane alone, say goodbye to your inhib. If you send 2 people to help the laner, making 3 man gank, then come on, you've got only 2 people left to defend the other two lanes against 4 other enemies, at which point you should ask yourself: is it even worth a risk? Especially when you take into consideration he has high chances of taking one ally down? What if enemy jungler comes at that time? That's just ez triple.

So I ask again: why? Why is he allowed to do this sh*t? Somehow Riot spared us the suffering of playing against old Yorick and old Poppy throughout the years 'till their rework, but Heimer can still make lives of other players miserable? Turn somebody's laning phase into cycle of frustration and rage? How is he not gutted yet for not only being unfun to play against, but being completely cancerous in the process? And as I said, mid Heimer is still managable by some champions. But top lane Heimer, I wouldn't wish my worst enemy to face against him while playing any conventional top laner.