X-Files...

[Kynch]

Originally Posted by benricci

Well, the assumption is that any blu-ray release would include newly created hi-def masters, transferred from the original 35mm elements. This may involve re-doing some of the special effects that were originally created in standard def, however.

That's the main issue. The special effects weren't on film but only on the master SD tapes, which can't be scanned at more than 1024x576i.
You really think Fox would spend tons of money rescanning the film but especially, redo the entire special effects? I think not.