It's an interesting world we live in where Apple is the choice for performance. For years and years everyone talked about how Macs were underpowered compared to their price tag.
Honestly, if AMD had access to the same silicon Apple does, there probably wouldn't be any comparison. I'd argue their processes are half a generation ahead of Apple's designs.
Though of course there are other comparison issues like the ANE and video decoders making certain tasks significantly more efficient, so testing the whole package does become much more complex to represent.