Since remastered versions of DS9 and VOY aren't happening any time soon, I think the next best thing should be a SD-BD release, kinda like how Discotek Media are doing with some old anime titles
TL;DR
TNG was filmed with actual film and converted to tape for vfx and broadcasting in SD. The conversation to blu-ray cost $10 million dollars as they had to redue all the special effects. Both DS9 and VOY were filmed the same way and no one at Paramount is interested in creating a physical remaster on blu-ray for limited sales it seems.
Op is taking about a standard definition release on blue ray, not the full upscale job the article is talking about. An SD re-release onto a larger medium is probably the best we can expect to get, but I'm doubtful even that will happen when looking at studios behavior
Yeah, not sure on audio quality. To my ears DVD audio is already in the realm of diminishing returns unless the mastering was done very poorly. No clue if they were doing 5.1 or any sort of multi channel on the DVD releases either.
The better quality because of more room for higher bitrate makes sense assuming they still have the final cuts pre-dvd-compression laying around. This could get you some crisper, less artifacty output.
But this is also just speculation on my part. I've never checked out one of these sd-bluray-re-releases myself.
They might be more interested if the TNG remastered sales were better. The pricing scheme on them was absurd and drove off potential customers, though. IIRC, waiting for the complete series set was actually more expensive than buying the seasons one by one as they came out.