It would've been smart for CBS to cooperate with them... which yes would've put the kelvin timeline (which again was supposed to be the future of the franchise) front and center.
In business terms, I think CBS made the smart bet here. It banked on the content it had a long history with (and a big archive of), rather than the new flash-in-the-pan version with questionable staying power. Really, the Abrams Trek films were always a little too clearly his "demo reel" for taking on his first love, Star Wars.
In terms of personal enthusiasm as a fan, I'm very glad the Abrams films were not treated as the solitary "future of the franchise." If they were, not only would that be a franchise in which I'd have little to no interest, but even if I did, the franchise would be pretty much dead by now. After all, if the Abrams version of Trek didn't quite catch on (as seems to have been the case), there are lots of reasons to look at before one ever gets to "competition from TOS merchandise."
The "Kelvinverse" is a sideline. A curiosity. A modestly successful experiment. It was never going to be the totality of Star Trek's future.
Beyond that, circling back to the OP...
I'm not sure why there's any reason to see it as a competition. Personally, I like comic books and comic book movies, and I think one reason the Marvel Cinematic Universe is going a strongly as it is is that, frankly, it keeps making good films. It has yet to make one that really screws the pooch. Even at its worst (say,
Hulk or
Iron Man II), the MCU is at least moderately entertaining; at its best it's amazing (
Avengers was one of the most legit four-quadrant movies in years). It has earned its cred with audiences. A decade ago, who would've thought that people would be lining up to see movies adapting
Ant-Man or
Black Panther?
At a sentimental level, as a fan, I don't have nearly as strong an attachment to Marvel's characters as I do to DC's, or for that matter to
Star Trek. But the Marvel movies are simply
better movies than the kludgy Zack Snyder DCEU films, and certainly than the Abrams Trek films. I give a lot of credit to Kevin Feige, who clearly knows what he's doing.
But none of that is actually in
competition with Trek, or obstructing Trek from being more successful. And certainly, "total hours of live-action content" isn't a relevant metric.
I'd love to see Trek be just as consistently entertaining as the MCU... the thing is, there's apparently nobody at CBS with the kind of devoted love for the property, and keenly honed creative sensibility, that Feige brings to Marvel. I had hopes for
Discovery... especially back when it involved people like Bryan Fuller and Nick Meyer rather than people like Akiva Goldsman and Ted Sullivan... but the first season was a very mixed bag, to say the least. Not as bad as the Abrams stuff, to be sure, and more entertaining than the first seasons of most past Trek spinoffs... but still, that's a pretty low bar. Lots of unrealized potential, emphasis on the "unrealized." But even if it's not necessarily "the future of Trek" in its own right, that doesn't mean that Trek doesn't have a future. It just hasn't found a solid creative footing yet.