Zed overrated?

Now Zed is always banned in my ranked games but I don't understand why he's considered so overpowered.

There seems to be this common belief that Zed is a very strong laner. Yet when you look at the most common picks in Mid you find that most of them can actually go even with Zed while many actually counter him very hard. His laning is nowhere near as strong as it is made out to be.

Also, Zed can be easily counter-picked not just by a mid lane pick (like Fizz or Yasuo) but he can also be counter-picked by a FREAKING SUPPORT. What other decent mid-laner can get hard-countered by a FREAKING SUPPORT?! Seriously, try playing a Zed when they have a good Zilean or a good Lulu on their team who has some brains and goes ... "Okay, Zed is about 50% of the damage from their team so I'm just going to hold my OP shields/revives for my carries when he Ults."

Zed is a HUGE ticking time bomb. Even if you destroy the other laner and get a few good roams and push a few towers... chances are that by the time it goes into a long game (and it almost always does because people in Solo Q just keep throwing), Zed will fall off. Zed becomes this very powerful (only at 1 vs 1) but RIDICULOUSLY FRAGILE assassin who can't afford to make a single misplay or else he throws the whole game. And for what? Just to kill 1 carry and probably die doing it? Even if he escapes... so what? He's unlikely to have the health to do anything after.

What utility does he bring at that point in the game compared to an AOE caster like Vladimir (who can nuke a whole team) or a Lux/Ahri (who can create huge play-making opportunities for the team). Whenever a team picks a Zed, they are in huge danger of creating a late game where they simply cannot team fight. And if they cannot team fight and they can't rely on their team mates not to throw while splitting... they will definitely lose.

And while yes, Zed is a strong split pusher, there just seems to be too many towers to push down. It takes too damn long. And in Solo Q when left with 4 people the team is just going to throw over and over and your lead will be squandered. Even if you try to TF as Zed, its likely to turn out bad simply because you can't afford to make a single mistake.

Yes Zed has a ton of damage (on paper) but because of the cool downs you can only 1 vs 1 unless your team creates oppertunities for you by wounding other key targets.... its also ridiculously risky because you have to get up close to get kills.

The other problem is that if the enemy ADC is smart, they are going to buy a Bloodthirster and a GA, and just stand in the middle of their whole team next to a Support who counters you (ex Zilean or Lulu). Then good luck ever assassinating them. You can't get the Mid Laner either because guess what? He has a Zhonya. So then what do you do?

In my opinion, I think Zed is highly overrated. A skilled Vladimir/Lux/Ahri is way more dangerous than a Zed yet Zed's ban rate is grossly disproportionate to his actual likelihood to carry.

Thoughts?