IMHO, the issue with DIS isn't that it's the Michael Burnham show - it's that it never quite commits fully to her, still trying to find excuses to use the core cast, even when it's not super sensical.
For example, look at Season 5 as it's developed. Really, the only characters on Discovery who are essential to the season besides Michael are Rayner and Book. Both of them are defined in large part by their relationships with both Michael (the protagonist) and Moll and La'k (the antagonists).
No one else has been given much of anything to do. Going through the cast:
- Culber perhaps got the best turn this season. His status as a doctor allows him to be plot-relevant in most episodes, and he got an interesting turn in Jinaal, which led to some sort of existential/spiritual awakening. The season teased some stuff with conversations with Book, but this went nowhere and vanished.
- Saru got put on a bus in his role as Federation ambassador and his engagement to T'Rina after the end of Episode 2. He got a fraction of an arc about relationship drama, but promptly vanished from the show (though he'll be back).
- Stamets had a tease about some sort of existential crisis with the spore drive being shelved, which went nowhere. He got one focus episode in Face the Strange, but otherwise he's been largely absent unless they cut to engineering for like 30 seconds of exposition.
- Tilly got a feature in Whistlespeak, but that role was interchangeable - anyone could have done it. Other than that, and some initial setup in the first two episodes, she really hasn't had a role this season other than to spit out exposition on the bridge.
- Adira got a completely unneeded/drama-free breakup scene with Gray in Jinaal (it's obvious he was put on a bus last season) and is otherwise barely above extra level.
- Going past the core cast, I could argue that the limited re-appearances this season of characters like T'Rina, Rillak, Vance, and Kovich has been much more perfunctory than in Seasons 3 and 4. They're present for a scene or two, and sometimes drop exposition, but nothing about them being there is integral (so far) to either the season's plot or Michael's journey as a character.
In the end, one can easily re-imagine the entire season, stripping all of this out. What if, after Episode 1, Michael was put on something more like a runabout with Book and Rayner, and they did the whole season as a trio? Most everything could work largely the same way. Jinaal could have possessed Book, with Michael and Rayner dealing with the puzzle in the valley. Book could have been the one trapped in the chamber with no air in
Whistlespeak. You can't
Face the Strange to work, because that requires the use of Discovery as a set (and the crew to be there) but otherwise, most of the season would work better stripped down to only three characters.
This is, IMHO, the core problem. Most of the cast of the show have no real reason to be on the show any longer, as the story barely involves them past their status as members of the crew - and most of them aren't even bridge crew. Hence the show keeps on having to come up with "excuses" to rope them in, scenes which, if they were in a novel, an editor would tell you to cut and/or simplify, because they don't add anything to the narrative.