I think one thing is absolutely for certain, and I can say with some confidence after 13 episodes now.
Star Trek: Discovery may be a great many things (including "polarizing"), but it is certainly NOT dull or stale.
We all like different things in Star Trek, no doubt. I, for one can like "The Inner Light, "Star Trek- The Motion Picture" or "The Empath" as much as I can enjoy "Wrath of Khan," "Conspiracy," "Best of Both Worlds" or "The Doomsday Machine." But, there are some people whose tastes and appreciations are not nearly as diverse (and that's ok we all like different stuff for different reasons).
But for me, the greatest sin of all with any Star Trek property is that it be dull and stale. Its one of the reasons I struggle revisiting TNG time and again, for example. As much as I adore TNG and those characters, it was SO rare that anything about TNG got my blood pumping. Sure, it's nice to sit thoughtfully and think about Picard's latest ethical dilemma, to smile at Data's quaint attempt to be more human, or to think about whether Janeway did the "right thing." But none of that is exciting. And, it's even less exciting when you do that 750 times.
DSC is pushing into new territory (thematics, storytelling, characters, tone, etc) and it is actually exciting to watch unfold. It is far from perfect, and it isn't sharp in every single storytelling area...but it's fun and it's exciting without question. To me, that's what I loved about TOS from day one...and I always hungered for that. And we never got it with any kind of consistency outside TOS and the TOS movies and (for some stretches at least) DS9. DSC is tense and exciting, and the formula is nowhere near that which we had over and over again by the end of the 90's and leading in with ENT.
Its not a knock on any version of Trek. It's simply an acknowledgement that the longevity of the franchise combined with a relative unwillingness to try new approaches led to a stagnation and lack of excitement for me personally. I know "exciting" and "fun" can be bad words for Star Trek fans who have had it knocked into their heads since the early 70's that this property is for intelligent, more refined viewers blah blah blah (what a bunch of horseshit)...but not for me.
Time will tell how well DSC holds up and how it is judged. I think there's a lot more time and a lot more story to be told before anyone is truly in position to do that, especially when you look at the discussion board post from the 1990's someone put up earlier that shows people were having precisely the same arguments about TNG's place in the franchise back then as we are about DSC now...it's almost funny how futile it makes all the discussion seem.