Looks like most of the cards in the top 20 support H.265 4:2:0 (NVidia 10XX and up), just not 4:4:4 (NVidia 16XX and up).

I don't think the steam hardware survey is a good sample of the wider computer market though - the majority of people using youtube/netflix/etc on x86 devices are probably using Intel laptop chips with integrated graphics, not $500+ dedicated GPUs.

(Although presumably this is probably becoming less true over time, those low end users are moving more and more to mobile devices and smart TVs/chromecast/console, leaving workstation/gaming systems to be a larger percentage of the market)

Actually, Maxwell (9xx) already supports hardware-accelerated H.265 decoding, but on first-gen Maxwell (the higher-end GTX 970/980 at least) it's not pure hardware decoding and didn't work on Linux last I tried.

> But I don't think desktops are the problem anyway as opposed to laptops/tablets

On the Apple end of things, h265 hardware decode has been supported since the A9 (iPhone 6S, introduced 2015)

They also list hardware decode support on Macs as of Intel 6th gen CPUs (Skylake, introduced 2015).