Great overview by Sebastiaan de With on my the Pro market should matter to Apple:
Without a truly top-tier workstation, Apple will miss out on a huge segment of digital creatives that can craft the future of human-machine interaction — something way beyond tapping a piece of glass. It would lack a Mac workstation with the raw computing power to prototype VR and AR interactions, build game worlds, simulate complex models and render the effects of tomorrow’s great feature films all the while offering those same creatives a platform to create for its own mobile devices.
These are all rational reasons. We have less access to the financial ones, but I’m sure they’re there. Lastly, there’s the feeling of coolness; of getting the right tool for the job. That’s a thing Mac’s are slowly loosing.
But it does seem that Apple finally noticed.