It's not just about coprocessors. If one CPU has a set of SIMD instructions that double performance on that benchmark or more, that creates a large outlier that significantly changes the average.

Apple Silicon also has more memory bandwidth the primary purpose of which is to feed the GPU because most CPU workloads don't care about that, but if you average in the occasional ones that does then you get more outliers.

Which is why the thing that matters is how it performs on the thing you actually want to run on it, not how it performs in aggregate on a bunch of other applications you don't use.