I have been hired essentially on the strength of a covering letter... weirdly, I was later cc'ed on a whole email chain going back to my application, and saw the impact of certain things I had mentioned.

It was basically explaining my passion for a cross-industry move. But for most people for most jobs, most of the time, a job is just a somewhat match for their skillset and there isn't much else to say. Now I'm hiring I don't pay much credence to cover letters or objective statements, but they can still be meaningful for certain people's circumstances. I think cover letters have a bad rep because a generic one is meaningless.

As someone who has done a lot of the hiring side for technical positions, I never care about a cover letter. I can't remember the last time I saw one.