What is Mordekaiser's weakness in lane?

Every champion has (or must have) a certain weakness that can be exploited in lane, certain counter picks or strategies. When you look at mordekaiser, the obvious weakness would be poke. He's amazing in all ins so the only way to beat him is poking right? The problem is... His E has more range than any ranged champs' base AA range (at 675), so simply poking with an AA every now and then will allow him to return the favour. On top of that, he has such great sustain because all his abilities create a shield, his W also gives a big chunk of health back and his first item is Relic's shield (while not part of his kit, his kit is already so fulfilling that he doesn't need a stronger early game item). On top of that, his support usually also runs relic shield or has some kind of shield/heal in their kit. In my experience, it's nearly impossible to poke down a mordekaiser (or his support for that matter, because he also gains sustain from Morde's W and Relic). Mordekaiser's statistics show this. He doesn't have below 50% winrate IN ANY MATCHUP. Even the greatest of poke champions can't deal with Mordekaiser. In the best case scenario, you survive your laning phase.

Susceptible to ganks? I think I've seen more ganks against Mordekaiser fail than succeed. He is so immensely powerful in close combat that even when you jump at him with 3 (incase he has support), he can still be the crap out of you. Incase he can't, he still has his W to safe himself or his ally incase the other one managed to get away already (usually they focus CC on one of both.)

The frustrating thing about Morde is that he litterally shits on certain champs (Melee supports mainly) but he doesn't even care about his counterpicks because his weakness isn't that great. IN most cases, he just heals back the harass while he or his support can return some harass or all-in engage at the slightest misposition.

There are some nerfs on the PBE and they seem to be tackling his sustain (slightly higher cost on Q, added a cost on W, lower healing on minions) but why are they compensating this by increasing his dmg on W? Both dmg over time and the big chunk! He's at 56% winrate, he doesn't need compensation. If anything, I think his sustain needs to be tackled more.