Let me input my own two cents here.
Tanks, in theory, are meant to be defeated when 3-4 people on the enemy team are focusing them in the late game. They should NEVER fall to a single opponent when even or ahead, with the only exception being
(because Vayne).
With that being said, tanks should not have enough damage to fully 100-0 their LANE opponent. For instance, a duel between Wukong and Maokai around level 10 should go in no one's favor because Maokai would get Wukong somewhat low, and Wukong would not have enough damage to get through his defenses.
I am perfectly fine with top-lane tanks being able to duel ADCs and mages and WIN, because unless you are ahead dueling a tank is STUPID in the mid-game. They're supposed to be tanky, AND have enough damage to successfully clear in top lane. With Nautilus, he clears with his Riptide. That skill has a reasonable amount of power. His ultimate and Q are mostly used for trading, so those are supposed to have good amount of damage as well. Take the damage away from those skills, and you're basically relegating him to a support tank, which he SHOULDN'T be.
Late game, when Draven has all of his items and the rest of his team, he should have more success against the Nautilus. In short, tanks that belong in the top lane are justified for having that kind of damage, because otherwise they wouldn't be able to lane against skirmishers, juggernauts, and divers.