I've often thought this. To support the current lineup of MacBooks you'd need to test on 8 CPUs, 3 GPUs, and have basic support for Mac hardware across the line

I've often thought this. To support the current lineup of MacBooks you'd need to test on 8 CPUs, 3 GPUs, and have basic support for Mac hardware across the line (keyboard, trackpad, webcam, etc). There might be some issues with writing drivers for devices that Apple has not provided any specs for, but once the effort is expended it'll work on a wide range of popular machines.