I so regret that because of the two different conditions and the two sides that have been achieved, I have a lot of time to wonder to myself if there are reasons about the state or certain regulations may require people to take compliance, and I regret it very much.
Nobody can answer it and the only fact we can say, and I believe it is always true, every Bitcointalk member have their own life, beyond the forum. By this, they have many different reasons to leave the forum.
Struggle to rank up?
Reason is they did not contribute enough to rank up. If they have good contributions, ranking up is not a big challenge for them.