By "unbeatable" they mean it lasted a few hours in the hands of the public before the hardcoded behaviors were exploited and it was defeated consistently. Turns out hardcoding the mechanism for players to manually block creeps (a more "creative" play style, but a fundamental element of lane control) allowed for the exploit. The bot did not teach itself to control the flow of creeps to gain a laning advantage against the opponent.
Not to diminish the teams' achievement. This was awesome. But again, it's just more over-hyping of AI that should be called out for what it really is.
Not to diminish the teams' achievement. This was awesome. But again, it's just more over-hyping of AI that should be called out for what it really is.