I don't think that's how scaling works. I believe Drastic (and other DS emulators) use interpolation for their scaling (i.e. linear, bilinear, etc. instead of nearest neighbour). You also have the difference between the scaling of 2D and 3D elements, meaning sprites and textures are handled separately (and therefore they need to be stored somewhere: RAM!)
But the original RG DS already underperformed when it came to DS (I believe Russ was able to run 2x with Drastic on the original in some games), having a third of the RAM certainly won't help for playing 4x integer scale DS. I highly doubt that Anbernic will make it work with their "NNDDSS" emulator