I think the youtube one is a a fake uprez. It's got the CBS/Fox logo and the video trailers present on my VHS copy. (Mine is the white logo box in the photo.) Even if they somehow got their hands on a video master, it's still standard def.
JEDIT:Even at 480p, it's blocky.
The other three docs may have been remastered for the 1995 Japanese LD releases, but SWTJ only had one LD release in the 80's. No idea if the later VHS releases were remastered.