Hello, TCS assistant professor here: he is legitimately respected among his peers.

Of course, because I am a selfish person, I'd say I appreciate most his work on convex body chasing (see "Competitively chasing convex bodies" on the Wikipedia link), because it follows up on some of my work.

Objectively, you should check his conference submission record, it will be a huge number of A*/A CORE rank conferences, which means the best possible in TCS. Or the prizes section on Wikipedia.

Not sure if you're trying to be provocative, but you could just click his name in the link you provided to find a lengthy list of arXiv preprints: https://arxiv.org/search/cs?searchtype=author&query=Bubeck,+...