Based on an attempt by a fan to remaster DS9 in 4K using AI upscaling, I applied his method to Stargate SG-1, and this is the result:
It's far from perfect, and definitely not true HD, but I believe it has potential for the future. Especially considering the series was shot almost entirely on digital video, it's impossible to truly remaster it to HD as with traditional film (which would also make DS9 and Voyager much more difficult and expensive, compared against the low sales of TOS and TNG).
I even think it wouldn't be necessary to redo the CGI. The vast majority still holds up even today (also since Stargate used a lot of practical effects). This would significantly reduce the costs, even if a minority of CGI shots did get replaced due to aging. If the raw unedited footage, or the raw post-processed footage (with the CGI), still exists somewhere, I would imagine the results to be even better, compared to the final DVD video.