HEVC is still in its infancy, specially in professional workflows, since it doesn't yet compress as much as expected maintaining a good quality.HEVC is not new. This update is way overdue.
There is no major professional camera manufacturer that has HEVC implemented as recording codec - and believe me when I tell you that I'm holding myself, waiting (in)patiently for a camera with HEVC recording.
HEVC has been mainly used in delivery formats, through transcoders, namely 4K Blu-ray discs, HDR, 10 bit color depth and Rec. 2020 color space - all of which were undoubtedly aimed at when designing the new iMac Pro. Other workflows were on hold, since te codec was very taxing on the hardware.
The new Mac line, launched this year, along with High Sierra, not only gives native support to HEVC, as they have the hardware processing power to handle HEVC.
Therefore, I think that the HEVC update, not being new, comes in par with what Apple and Intel have been doing.
By the same logic, with new chips, whether for computers, or imaging devices and recorders, I believe that HEVC's implementation will be broader. Those of us who work in 4K, do need it as soon as we can get - whether for recording more time in less memory, or work with it in post without the need to time consuming transcodes.