[ogogmad]

Yes it did, except all of those examples where it convincingly helped were super-advanced, very hard to comprehend, and lacking in non-niche applications to CS or physics.

There is a category theory "school of thought" in certain subjects, but it's usually a speculative belief in the importance of category theory.

[bubblyworld]

Improving communication between experts in a niche discipline is also a value-add, in my opinion (and my experience, for whatever that's worth). There's no need for it to have mass appeal to be useful.