In gaming they are just at 1.61% right below 1280x1024 and the increase is so low (+0.01) that might as well be zero (compare with 1080p's +2.04% which is the one increasing the most):
Tech minded people are a bubble, gamers are a tiny bubble among those and /r/pcmasterrace 4K-or-die boasters are a tiny bubble among gamers. 4K, or even 1440p, matters way less in practice than tech minded people think.
There is basically no upper bound to the display resolution people want, even if their eyes can't physically resolve it. Graphic designers and gamers will still swear there's a difference. It's like audiophilia for the visual system.
At a certain point people will prefer large and more monitors over increased resolution. If I could buy two 16k monitors instead of one 32k monitor I'd do it, and that puts a soft upper limit on the resolution.
Again, where's the proof that the performance is a problem? The standard library should solve for the 80% case. I suspect it is well within "fast enough."
If you need speed don't use the standard library, use something specialized.
This is a great example I didn't even know about that reinforces why I like Go. We don't have to over engineer everything.