I often see people claim - including latter-day Trek writers - that TOS was about "the characters" - particularly the Kirk-Spock-McCoy triumvirate. Nothing could be further from the truth however.
TOS was about as character driven as
any action/adventure show produced in the '60's. You may be comparing TOS to a modern character driven show and by that standard, no, it doesn't look like it was "about" character. But for the writers who worked on that show, from their viewpoint, which is just as valid as yours, they wrote a "character" show.
Basically, Trek started out as the Twilight Zone on a starship. It ended up Lord of the Rings on a starship.
FWIW, TOS was never "the Twilight Zone" which was a a true anthology series with different characters, actors, stories, and set in different eras. Not sure what is meant by the Lord of the Rings reference.
As much I hear fans clamor for something new what I often see being the money maker, or in fan works, is what we are getting.
Back when I frequented the Star Trek forums on AOL back in the early '90's, there was much talk by the fans about wanting to see some "new" things in Trek, like sex, darker stories, even a desire to see Klingons speaking Klingon, among other things. But after going through Ent's run here in the Ent forum, my conclusion since then has been that Trek fans truly DO NOT want anything new.
The complaints about the new races in Ent, like the Suliban and in particular, the Xindi (who according to fans, should have been the Romulans), ranged from "uninteresting" to "this is a prequel, so where are the old races?". Something to be said for both sides of that argument, but what cannot be argued is the fact that fans love what is familiar, and that a prequel offers an infinitely logical reason to explore the familiar.
But, as can be seen in this very thread, some, not all, and certainly not the majority, continue to drag DSC, which is a prequel, for logically exploring familiar characters and themes (or "fanwank" as some call it).
So, I guess the argument that is really being made by some, either consciously or sub-consciously, is for a 24th century (or beyond), show. That's fine. But, DSC is a prequel, and as such, needs to explore historical Trek stories in greater detail than a 24th century show could offer.
I'm still struggling to figure out why Discovery needs to be in the Prime Universe from a story point-of-view?
For me, arguments about whether or not DSC is in the Prime or Kelvinverse are as boring as arguing canon. What difference does it make to people which universe DSC is in, other than providing some folks a reason to be "outraged' or even "offended".
Heck, I'm still struggling with why it even needed to be in the 23rd century. You could have changed some names and it would have been indistinguishable from 24th century Trek.
It may seem that way to you because all of the 24th century shows were produced in the '80's and '90's and therefore, looked like space faring shows produced at the time. DSC, season 1, was produced in 2017 and looks like a 2017 representation of the 23rd century. People still seem to be a bit flummoxed by this.
They apparently think a 2017 or even a 2009 representation of the 23rd century should look exactly like the representation of that era by shows produced in the '80's and '90's despite inevitable advances in production technology. Makes no sense.