Why is it cheating? We literally teach sports this way? Often times you teach sports by learning in scaled down scenarios. I see no reason this should be different.

If the goal is to learn how to solve a Rubik's Cube when you've never seen a Rubik's Cube before, you have no idea what "halfway solved" even looks like.

This is precisely how RL worked for learning Atari games: you don't start with the game halfway solved and then claim the AI solved the end-to-end problem on its own.

The goal in these scenarios is for the machine to solve the problem with no prior information.

This isn't accurate, though? Halfway solved, for most teachings, is to have the first layer solved.

Indeed, this is a key to teaching people to know how to advance. Do not focus on a side, but learn to advance a layer.