Though I'm fairly confident that self-confidence is required to 'move up to' Alpha, not everyone with it gets to move up, in that the social group has the decision more than the individual. While I'm sure that after transition many people will become more self confident, I'm not sure all do. Moreover, if 'transition' is a reason for that, so can lots of other things in life. And things change over time, sometimes so slowly you don't really notice till it gets kinda big.
And, I really, really wonder if the decision to transition or not is not an Alpha decision. So that among the people who do transition you have a higher population of Alphas then in the general population at large?