I don't think the comparison with aimbots is fair. Aimbots are more like a perfect micro. In the beginning (when they did their first show match), Alphastar was insane at that. Now the micro is not giving an advantage anymore.

Where alphastar shines, is in making a strategy work. It won't attack into something that looks dangerous. It won't forget to build more units. It won't be distracted on two fronts. (That said: Alphastar did some really stupid mistakes as well.)

I agree with you, though: it would be much more interesting, if Alphastar was actually handicapped in the micro (at least at a later point in the game). Then it would really need to find interesting strategies and counter opposing units with more cost-efficient ones.