Why doesnt the Catholic Church demote Mary to "normal" so that they'll get more converts?

They would have to change a lot more than that, like not making birth control a sin. Catholics say that using birth control is like "playing God", but isn't that placing a limit on God's power? I am more than certain that if it is God's will to give a couple a child, it will happen, birth control or not. The Catholic church will not change for anyone, either you confirm to it, or you don't confirm at all. Not a bash, just the truth.