Just how long do you think it takes to discover they have an aptitude for magic? Savants can pick up and discover their talent immediately and it is why people get sent to places like Dalaran. While people study tremendously as mages to hone their craft, discovery has always presented itself as instant in novels and stories and younger NPCs especially - lots of children in the Mage District in SW, for example.
Besides, Tauren enchanters, inscriptionists, already existing Grimtotem mages, and Runemasters say hi.