A little bit of Apple hagiography in there, claiming Apple is usually first. Discrete video cards have consistently been at the forefront of features like this, leading Apple by years. The difference is, the consumer must decide to build a system with these features. If I want an HDR system, I buy an HDR capable discrete card, HDR capable monitor, etc and put it all together.

What Apple does is assemble it all in a base model, like a console, so that all models have the feature set as base. And like other commenters have pointed out, PCs with HDR have been shipping long before, especially "workstation" machines.