What they did here is one of the first steps towards an AI that generates nontrivial and correct mathematical proofs. (An alternative benchmark would be IMO-level inequalities. Other topics such as algebra, combinatorics and number theory are probably no easier than the rest of mathematics, thus less useful as stepping stones.)
And an AI that generates nontrivial and correct mathematical proofs would, in turn, be a good first step towards an AI that can "think logically" in the common-sense meaning of the word (i.e., not just mess around with words and sentences but actually have some logical theory behind what it is saying). It might be a dead end, but it might not be. Even if it is, it will be a boon to mathematics.
And an AI that generates nontrivial and correct mathematical proofs would, in turn, be a good first step towards an AI that can "think logically" in the common-sense meaning of the word (i.e., not just mess around with words and sentences but actually have some logical theory behind what it is saying). It might be a dead end, but it might not be. Even if it is, it will be a boon to mathematics.