I'm not that surprised. The show's very nature gives it a limited shelf life. Part of the fun of Trek is watching the characters develop and advance in their careers. Eventually they're gonna get promoted past what can be called lower decks.
I'm a bit pissed off that they're canceling this and going ahead with the section 31 project, but I find section 31 to be tedious at best, and that it undermines Star Trek's message at worst. "Your utopian post-scarcity society that celebrates diversity can only exist because of these unaccountable fascists slinking about behind the scenes."
Section 31 was a cool concept in ds9 because of the context around it.
Every other time 31 shows up is just... Blech. Feels like those writers want to be writing something bloodier than star trek and this is their way to do it.
My biggest gripe with discovery was the secret plot to blow up the Klingon homeworld foiled at the last second. Almost turned me away from it entirely but they got much better. SNW is up there with TNG for me now.