I just feel like the whole people who are pro AI here have lost the plot.
Fans who did the AI upscales did them and offer them up on the internet, because there isn't an HD image to begin with.
The studio in either case would upscale the master tapes to start using them as a template to match takes to, that's part of how they remastered season 2 of TNG, generally, the foundation is a bicubic upscale, that iConform matches takes of the image to.
It was deemed unacceptable in 2010 to do that, the sample of that footage is also available on TNG's bluray release.
From what can now be seen with Roseanne, Aliens and True Lies 4k, it's just an automated enhancement algorithm that can sometimes redraw faces (Badly).
Diffusion upscalers are kinda worse, even on HD footage, I tested a clip from Emissary that was remastered for WWLB, and it literally removed Terry Farrel's teeth.
I feel that the upscaling movement in general comes from a place of cynicism (That there possibly won't be an HD master of the series), and the product that results from just upscaling it, is also extremely cynical, and the studio would only be able to output an upscale inferior to something a fan can do with mediocre sources.
At this point, the studio doing it is almost as tone deaf as a laserdisc transfer of Star Wars going to DVD.
Fans wanted the original '77 cut, and for a very long time, there wasn't a legitimate scan of it to look at.
As for a rebuild of the show, part of remastering is rebuilding the master from pristine sources. That's literally what constitutes a good remaster.
On a technical level, you could call an AI upscale a remaster, as it's cleaning up the master, but it's digitally enhanced.
From what I gather, fan upscales are freely available, and would look better than what the studio would offer, as the studio would bake deadlines in.
If the studio were to release something like that and pass it off, it would be very insulting.
I've seen some of what CandyBoys did with Voyager, and the AI can't discern if 7 of 9 is male sometimes, it's jarring.
So the most valuable part is an actor's face.
Personally, from the few HD clips I've seen from WWLB, there's nothing wrong with DS9's production value, it's beautiful, and I think you're robbing fans of Star Trek if you do a simple upscale at the studio level. From the costumes, to the sets, to the color, it's not some sickly green, there's a vibrancy to that. Even the makeup looks HD ready, Quark looked excellent in HD, as did the Cardassians.
The costumes looked amazing, and the props looked very good.
It's nice when a fan can do an upscale, it shows the fan's love and dedication to the show.
If a studio does it, it's a very terrible thing.
The template is simple, scan 35mm, grade, fix, edit (that can be automated) and let the people who love it, enjoy it.
There's a natural HD image there that probably wouldn't look good past 2k, 4k max.
The X files would be pointless in 4k, but it looks fine in 2k.
Bare minimum you need a good 2k source for a good upscale.
But there is another issue, your brain can identify facial expressions and knows what an upscale is supposed to look like for the most part. When an upscaler gets it wrong, your brain just knows, it can see it. The upscaling algorithm is far less sophisticated than a human brain, we've made great strides, but not yet does it look great.
The problem with "cutting edge" tech, is that it's still inferior to a substrate like 35mm film, or 16mm film, and smears detail, it has no sense of depth, and no sense of how grain patterns are different from skin.
In fact, the texture of skin is a big deal for me, little white hairs and other odd things happen, where the skin looks like some rubber reptilian carpet hybrid.
It struggles with teeth, and eyes, the big thing, the window into the soul.