To what extent do you think that 4K gaming has penetrated the PC market? The last survey carried out by Valve reveals that only 1.33% of Steam users actually primarily play at 3840x2160 pixels. As of September 2018, more than 60% played at regular Full HD resolution (1920x1080).
Unfortunately, there is no info about the displays being used, so we don't know if these numbers are related to the availability and affordability of 4K displays or to computing power, or if it's simply down to people spending a lot of time on games that don't require higher resolutions or online games where a smooth framerate is preferred over resolution.
Valve does tell us that GeForce GTX 1060 was the most common graphics card (14.29%), followed by the both GTX 1050 models. Just 1.54% of Steam users had the GeForce GTX 1080 Ti, the most powerful GPU while we wait for the new RTX 20 series to launch.
There are a few more interesting statistics. For example, Oculus Rift beats out HTC Vive by more than five per cent, and Windows Mixed Reality is growing at a steady pace and now sits with 7.22% of the VR market share, still, the virtual reality section of Steam is still rather small.
English is the most common language (37.23%) ahead of simplified Chinese (26.38%), Russian (10.67%), and Spanish (4.48%).