In my own case, I moved from LJ to Facebook not because of any change in LJ policies but because I found myself naturally gravitating to Facebook. More of my friends were on Facebook, the UI was better for social stuff, and I found that I was more interested in writing shorter status updates than I was in the longer blogs that were popular on LJ.
Over time, I posted on Facebook more and more and LJ less and less. It got to the point where I'd go months and eventually years without touching LJ.
I think the last time I posted anything was in 2009. The last time I touched it at all was in 2011 or so when I had a phone interview with someone, and the interviewer said he saw my LJ and he made jokes about it. So after the call, I found a script to mark every post on my entire LiveJournal as friends-only, ran it, and threw a line in my bio saying that everything in there is years out of date, and that was that.
Over time, I posted on Facebook more and more and LJ less and less. It got to the point where I'd go months and eventually years without touching LJ.
I think the last time I posted anything was in 2009. The last time I touched it at all was in 2011 or so when I had a phone interview with someone, and the interviewer said he saw my LJ and he made jokes about it. So after the call, I found a script to mark every post on my entire LiveJournal as friends-only, ran it, and threw a line in my bio saying that everything in there is years out of date, and that was that.