And it is an EXTREMELY WEAK argument to say that TNG-R failed due to low home video sales. There are multiple options for revenue for CBS with TNG-R that are much bigger sources than Blu-Ray/Home Video. There's conventional broadcasting, internet download (iTunes, Amazon Video on Demand), streaming (Amazon Video On Demand, CRAVE TV), and with conventional broadcasting and streaming CBS and the stations are able to sell advertising slots for a lot more than they can charge the average consumer for a download or Blu-ray.
Sure, I think you would get general consensus that if CBS took into account all future revenues of TNG then at some point it will break even. As I've said before even John Carter will eventually (and heck, I actually liked John Carter).
The thing is, somebody will point out that, whisper it, a lot of the show hasn't dated terribly well, and it will struggle to win new audiences in a TV market where it has to compete with Breaking Bad, and its cousins.
They therefore are not expecting thousands of new converts to TNG, but a solid streaming market for the show based on nostalgia, and those of us who remember it first time, and, whisper it again, they probably would have got that without the remastering.
So basically, their biggest and best chance to make actual profit from the remastering itself, not future sales of the show they would likely have gotten anyway at least for a few years, was the Blu Ray sales, which were crap.
DS9 would be far more expensive to remaster, for far lower sales, and with much less interest for future streaming markets. It was never as popular as TNG and while I suspect it probably would stand up better storytelling wise in the modern market than any of the other shows, I'd be amazed (but pleased) if we got a remaster at this point.
Bottom line, it won't pay for itself in three years, so it won't happen, its business.
But with 4k streaming already occurring, and 4k broadcasting on the horizon, CBS is going to need to offer DS9 in HD, because stations and people are not going to be interested in upconverted 480 video, and revenue potential for DS9 and Voyager is going to dry up.
You are assuming there that it hasn't already, there is far less concern for the other two series. It is no coincidence that the two series that were remastered (TOS and TNG) are by far the most popular. DS9 and VGR likely also had much lower DVD sales, and are less popular in streaming.
So CBS have over 300 episodes of Trek product to sell in HD, and you Mr Netflix can have DS9 and VGR in SD for cheap to get trek fans to sign up.
CBS can now take their millions and invest it in new serialised shows about anti-heroes!