An iPad Pro's single-threaded geekbench performance is better than the 8th-gen i7 in my laptop, according to geekbench. Multithreaded is better on my laptop. This is comparing the iPad to just the CPU; my actual model is almost certainly better (particularly if you consider thermals). This comparison is also with Apple's additional (not inconsiderable) design work on top. I also sincerely doubt an iPad could sustain this. But the point is the same: an a12x macbook pro could be a serious contender.