At the same time, I don't think we can expect any online service to be online in perpetuity. Someone has to pay to keep those services up and who still plays LBP on PS3.
They were probably paying an amount every month to keep it up, for maybe... 50 players? Players that bought the game years ago and have not paid anything since, except if maybe PS+ is giving the money. And even then, its probably far from profitable.