Yup. Microsoft kind of screwed itself on its own marketing here. Both the MacBook Air and the Surface Laptop 2 have a Core i5, but one is a Y-series chip, and the other a U.
MacRumors should amend the article accordingly. The Surface Laptop's CPU is only 2% faster in single-core, but 69% (nice) in multi-core.
If you google the perfomance tests for these two machines, you'll easily notice that the Surface Laptop offers dramatically faster speed for pretty much anything. So the Surface Laptop is a more affordable machine (depending on your region it's a dramatically more affordable machine, as Macbook Airs don't start at 1199 in Europe, for example) and it's much faster, and has a much better keyboard. Depending on your personal requirements, of course, you either have to choose between a slow, expensive computer that runs MacOS and a fast and inexpensive one running Windows. I suppose most people here will prefer working on a slower computer just for MacOS.