> On the one hand, this article is talking about the hierarchy of "physicality" of various mathematical concepts, and they put Cantor's real numbers at the floor. I disagree with that specifically

I didn't mean to suggest that the reals are the floor of reality, rather that they are more floorlike than the integers.

> The other question is whether Cantor's conception of infinity is a useful one in mathematics. Here I think the answer is no.

Tools are created by transforming nature into something useful to humans. Is Cantor's conception of infinity more natural? I can't really say, but the uselessness and confusion seems more like nature than technology.