I disagree with you. It does take creativity and actually it is the same in math. Many proofs have a little "trick" that required in my opinion creative or out of the box thinking to discover. That is the same for many leet code problems, and I'm already accounting for knowing data structures and algorithms, most people learn those at university.

I just want to mention though, I am not trying to criticize "your interviews". It seems like you put quite a bit of thought into it which i think is great and every interviewer should.