Trivial may not be the best word but what they were trying to get the AI to do was learn dota strategy and tactics. It's like teaching alphaGo to play go with a camera.

I disagree. The representation of state is hard for machines. Go/Chess are very simple state wise when compared to Dota. By giving it API access you have eliminated guesswork/approximations from the overall picture

I apologize if my statement was misleading. I do not think the visual problem itself is trivial. I think the choice of input mechanism is tangential to the hard problems actually faced by the AI designers: strategy and tactics.