I'm saying it's an edge case you shouldn't optimise for. Otherwise, if you're displaying an image at 640x480 CSS pixels, how wide should the image be in pixels?

I'm saying it's an edge case you shouldn't optimise for. Otherwise, if you're displaying an image at 640x480 CSS pixels, how wide should the image be in pixels? 2,000? 3,000? 10,000? Maybe each image should be 10MB just in case the user zooms in that far? I think you should optimise for regular display size and density.