GTrusted

To compete with the Xbox One S, Sony released the PlayStation 4 Pro which also supports 4K and HDR10.  Unlike the Playstation 4 Slim and PlayStation 4 which supports HDR10 through HDMI 2.0a but at 1080p only, the PlayStation 4 Pro supports the more standard HDMI 2.0a 4K HDR implementation.

The PlayStation 4 Pro is an important architectural upgrade to the PlayStation4 platform which probably didn't have the graphics processing power to handle heavy 4K.  Its higher processing power should be able to better support the Sony PlayStation VR although 4K and HDR is not used when experiencing virtual reality.

It's interesting that Sony has taken a strategy where the PlayStation 4 Pro doesn't support 4K Bu-ray unlike the Xbox One S which does support 4K Bu-ray.  In the past, the Sony Playstation 3 was the first game console to feature Blu-ray technology but perhaps this time around they sense a change in the wind.  Sony promotes NetFlix support on their PlayStation 4 Pro website and is also heavily promoting its own PlayStation Vue streaming service.  You can also see hints of Sony's position on 4K Blu-ray by introducing the Sony UBP-X1000ES 4K Blu-ray player much later than everyone else and targeting the professional A/V installation market and not general consumers.

Sony's strategy with the PlayStation 4 Pro is certainly focused on promoting virtual reality and 4K gaming which it sees as a much more promising market than 4K Blu-ray.  Sony also has at least a year before Microsoft Xbox releases Project Scorpio which also supports 4K games and virtual reality, so it makes sense for Sony to take as much market share from Microsoft in the meantime.