Maybe best foreigner (non-Korean) Protoss player. The match that AlphaStar lost had actions restricted to a single screen. Before AlphaStar could see and control everything that was not in the fog of war simultaneously. Still quite impressive though.
I agree with you and would like to add that he is probably not the best non-korean Protoss either. The blog presenting AlphaStar itself only claims he is one of the worlds strongest players and link to this post: https://liquipedia.net/starcraft2/2018_StarCraft_II_World_Ch... showing Mana at 5th best non-korean Protoss players in the World Championship series.
AlphaStar has gotten critisism for it having unfair advantages. It was 5-0 against Mana when it could see and control the whole map at once for example. But after a camera-restriction was given (so it sees the map like humans) it lost 0-1.
With all this said, it is still impressive. Best bot we have by far in sc2!
Less than four years ago our state-of-the-art RL system (DQN) could only beat some Atari games. Now we can almost beat best human player in SC. That to me is very impressive.