I don't think licensed pinballs alone attract too many new players. There must be something more there which catches the eye or ear of a new player. Most of the older players grew up on EM and early SS pinballs when there were more unlicensed than licensed titles. Nice art and sound of pinball in the wild was the key factor to pinball popularity over the past 50 years..
These days, I  see younger players turn a blind eye to a lonely pinball machine and head straight for the car racer and shooter games.