Morde is no hypercarry though. If his team kills dragon it's because they earned it or they stole it. If they stole it, the enemy is at fault for improper warding / focus. And so what if he gets dragon? You have a minute and fifteen seconds to do as much as you can with a super tank that has extremely slow, low ranged attacks. Yes you can take turrets with it, but you forget that if you kill him, you kill his pet. Also, if you'd rather just let him tramp down mid with a dragon by his side, then why not capitalize and get other objectives?
Okay so I see where you're coming from. Yes his kit is ridiculously strong, but it's fairly easy to counterplay him. If a PRO TEAM makes a mistake, it's going to be capitalized on for 200% of the real mistakes cost, cause they are professionals who know what they are coordinated. Just cause one guy did well against his enemy and one team stomped the enemy using morde does NOT mean that morde was the huge reason why they got stomped. It's just like any champion that gets fed.
Oh katarina got fed? She can pentakill in 3 seconds flat? TSM stomped LGD with katarina cause she got fed and now she's broken?
Obviously she's not, but I'm just trying to serve a point..
Also about that early/mid game power... He's also still pretty squishy early/mid game. Late game is when he has more hp-ap items. He's fairly easy to nuke early on if focus is proper (granted he's a problem?).
TLDR; Yes he is strong. No he is not the reason people win games - Teamwork is.
The only thing I can agree on being overpowered is how LONG the dragon lasts for. Other than that he isn't a game changer...