Anyone who thinks upscaling a SD video is even remotely comprable to remastering the original film in high-definition compare the old SD DVD version of TOS played on a blu-ray player to the remastered version. You can upscale till the cows come home, it's never going to be anything but standard definition.
It's like copying a cassette recording
onto a CD and expecting all the hiss and noise to go away and for it to sound like it was remastered. All the hiss and noise from your cassette is going to be copied onto a CD as well.