The fact they're so up front about asking it means they're aware it's become a negative space for lots of people. I'm guessing the huge amount of data they have (such as average log in sessions and type of interactions) is showing a large group of people either being put off completely or if they still use it a lot, not having a good time while doing so.
I have been using facebook less and less for the last year as I do believe it has grown into something that actually makes many people feel worse the longer they are on it.
It still has use for contacting people or arranging events, but there is now so much negativity on there that seems to be reinforced by design.

Edit: great first picture by the way, there are some people for whom it literally is like a drug they can't get away from, constantly scrolling the wall.