The lack of an option to change how images are scaled drastically limits what direction developers can take games on Roblox aesthetically. 8-bit/pixel is out of question. There should be a property in ImageLabel that lets us choose between NearestNeighbor and Bilinear (and maybe more).
The scaling has to be done in a third-party program, such as Gimp. I think with how Roblox currently handles scaling, which I believe is on the website, having a scale option for ImageLabels is generally out of the question, unless you want to reupload each asset. A better request would be to have an option on how the image is scaled at the upload screen.
Just set the Scale option in the export menu to “None” and scale your image up to 1024x1024.