Yeah, I was surprised too when I heard that, but if you had a huge database of HD movies, you could train a NN yourself, see how it upscales, use some algorithm

Yeah, I was surprised too when I heard that, but if you had a huge database of HD movies, you could train a NN yourself, see how it upscales, use some algorithms or different error functions to correct weird artifacts and put the trained weights on an FPGA.