I imagine the airlines that stopped pre-boarding because the elites don't like it was because of the abuse of the system. Last time I flew on AS there was a family with 1 infant (no carseat even, she was a lapchild) and 5 adults. Why does the whole family need to get on early for that? Plus there were numerous families with the youngest at least 5 or 6 when AS specifically says 2 and under.
Don't get me wrong I'm ok with preboarding, but unless you're installing a carseat, there's really no need to get on early.