Film's still got a ton more latitude than any other originating format, so I don't know where you get off dismissing it. Maybe when there is a 4K TV set in ____ years, you'll be able to really SEE just how much info there is on a 35mm film frame.
If TNG is in decent nick on film they did a TERRIBLE job of putting it on DVD, same for DS9.
I'm clearly not dissing film full stop but Trek does not look good on DVD, and was put together with a bit of care, so logically without a massive amount of work it would not look good on Blu Ray.
And it wasn't CHEAP either ... stock price is such a concern that some pictures shoot 3-perf instead of 4-perf to save 25% of the film cost (they will sacrifice that much just to be able to shoot on film as opposed to digital capture.)
Well I don't actually remember saying they should drop film in favour of digital anywhere, I was just talking about the apparent quality of the masters used for the DVDs.
Now with a complete remaster, including rebuilding the SFX, going back, rescanning and cleaning up the negative and really doing a super job, I'm sure all the shows would look amazing. Would cost an absolute fortune though.