I don't think I agree with that at all. If you can control 1 unit it's trivial to control 100.
I might argue that the AI vs AI challenge in Starcraft is deeper and more difficult to master. But for AI vs Player the Starcraft AI has an enormous mechanical advantage. Being able to harass mineral lines in four different places is a big deal. Being able to perfectly micro multiple lines of attack/defense is a big deal. It's very unfair and very much in the AI's favor.
The developer of the AI in this video even states that this AI is applies 300 APM per unit. That's 30000 actions per minute. There are simply not enough decisions to make in League of legends to make use of that power.
I might argue that the AI vs AI challenge in Starcraft is deeper and more difficult to master. But for AI vs Player the Starcraft AI has an enormous mechanical advantage. Being able to harass mineral lines in four different places is a big deal. Being able to perfectly micro multiple lines of attack/defense is a big deal. It's very unfair and very much in the AI's favor.
Chess < Go < Starcraft < League of Legends
In my moderately educated opinion.