So I use OptiFine, and it has an option to make screenshots 4x bigger, but 4x is not enough at 1440P...
So how do I run Minecraft at a higher resolution?
(also, does this thread fit here?)
I don't think you can, unless you have a way to specify a resolution higher than your monitor like you can do with virtual screen on linux (but it does not work for minecraft because most of the times it disables opengl, at least for me)
use desktop super-resolutions, should be in the Nvidia control panel or Radeon settings depending on your GPU