After closing the survey with the 3.5.1 release, here's the results from 15000 users reporting:
The big numbers (3.3 survey results in parentheses)
61% (57%) of the reporting users use a graphics card which is DX12/Vulkan compatible.
34% (34%) of the reporting users use a graphics card which is at least OpenGL 3.3 compatible, i.e. it can use the modern core profile render path.
This is further split up into 19% running an OpenGL 3 compatible card and 15% running an OpenGL 4.3+ compatible (i.e. capable of running the most modern render path) card.
2.5% (6%) of the reporting users use a graphics card which only has OpenGL 2 support, i.e. has to be run the legacy build.
No separate reports were made for the software renderer anymore.
Distribution of operating systems is:
90% (88%) Windows
1.9% (2%) Mac
8% (10%) Linux
0.3% are on Windows XP - most using the vintage build.
87% (85%) use 64 bit on a 64 bit system
9% (10%) use 32 bit on a 64 bit system. (This one's odd, I'd appreciate if some of these users can tell us why.)
4% (6%) use 32 bit on a 32 bit system
I think the most interesting aspect in here is the sharp dropoff in users on systems with OpenGL 2 and OpenGL 3.1. It more than halved over a mere 4 months!
This speaks a very clear language about the future of support for this hardware group. If the dropoff continues at the given rate and factoring in the Christmas business this will most likely not be supported past 2019.
Windows XP user share has already reached numbers where supporting it makes no real sense anymore - the exact number as of this morning was 48 users out of roughly 15000. As long as there is no need to reconfigure the project it will remain supported but I give no guarantees whatsoever about for how long.