I would not personally consider that to be likely, in no small part to the fact that a good third to a half of the magically active are those who follow more naturistic paths, and among those who revere nature were the magical arts first and most highly recognized. You might make a fantastic salary of 400k as a wage mage, but you're still generally being directed by a spreadsheet and a mundane, whereas in a tribal society you might well hold a position of nobility, honor, and influence as a judge, a communer to the spirit world, medicine-man, however you want to put it.
I don't deny that 'more people = more mages', or even that mages will tend to cluster; dealing with mundanes all the time can be a major headache, and it's nice to be understood by a fellow-astral-sensitive, you know? But I wouldn't personally call it more than a percentage point or three in either direction.