But as
@Smutley said, the Blu-Ray will be better than the DVD because the studio has access to the original high-resolution source material. It's not better because of some mysterious "upscaling" process.
I've done some comparisons too. For example, I watched "The Day the Earth Froze" episode of MST3K off of YouTube. Then I watched the actual film in 4K in theaters, when it was recently redone. It's pretty fucking obvious they didn't toss some "upscaling" on it and call it a day. (In fact, I just read the national audiovisual institute's report on the digitalisation. They
specifically mention working at highest resolution the film scanner was capable of outputting, all the way until the final mastering phase.) ...for starters the American version has several scenes missing and it's in a little bit confusing order, but hey, let's not complain about little details.