Incredibly dumb, yeah.
Speaking of dumb - Supergirl this week was surprisingly not dumb.
Both the show and the character
First, we get actual development in the form of Kara realizing that, yeah, she's not a good reporter. But she and Snapper at least know that it just needs some cultivating and it led to a nice moment.
Although, and this is something I blame the writers for, Mon-El didn't need to be the one to help her. It would have been a stronger statement if she had done the investigation on her own.
Since all of the leg work Mon-El thought to do, and Kara didn't, makes her look even less capable.