This trailer was their attempt to acquaint new audiences to the various characters. This is a common (and solid) marketing tactic that gives nothing away, but is intended to make people want to learn more about these characters.
I'm not sure why that would be a turn off to you. Maybe avoid it when you're in bed with your significant other, I guess?
As for it "not telling you what it's about"-- keep in mind we're still 2 months out. This is not meant to be a commercial for the pilot itself or a true trailer. This is a build-up/buzz-garnerning promotional spot to let broader audiences know it's coming.
For comparison's sake, here's the original promo for TOS, which like this DSC spot effectively sets the tone without saying or showing much of anything.
Here's a similar one for TNG, which shows NOTHING from the actual show, opting instead to impress with scenes exclusively from the films, which at best is misleading, and worse, false advertising...
Here's a series of ones from DS9 that are all incredibly vague. But skip to :53 to see one very similar to this DSC spot, showing quick glimpses of the various characters while talking more about the tone of the series than the story.
Now, maybe none of these get you excited either, maybe they too turn you off, but the point here is that these types of spots are common, and probably not aimed at the likes of you and me, who have been following the development of this show for the past 2 years.