Now, I allow myself back on only from a computer at home. I've removed it from my phone. It's still bad, but it's less bad. It saddens me, because I do like keeping up with old friends and new (it's especially great to see people that I lost contact with decades ago, and to keep up with the lives of my sisters and nieces and nephews some).
In the place of all that FB time, I've developed a love affair with my Kindle. I carry a paperwhite with me, and also the Kindle app on my phone, so I have two books going at once. It's so much better for my mind!
Today's two books: Strange Stars: How Science Fiction and Fantasy Transformed Popular Music, by Jason Heller, and The Better Angels of Our Nature, by Steven Pinker.
So yeah, the "value they get from reading" matters a lot. And Facebook has poor value relative to the addictive qualities and bad social habits they design into it. When I came back after my hiatus, FB put me through a quiz, and in an open answer section, I said flat out that the addictive nature was a serious problem. A little hook is good, but not too much! I think I said they should be selling candy, not heroin.