I can extrapolate from data in jurisdictions in which flavours are freely available, and the actual use of electronic cigarettes by youth is exceptionally low. It's less than 0.1% in a huge population study in Germany.
We can emphasize the small use of electronic cigarettes by youth or we can choose to see that the real problem is that 14% of youth are getting hooked on tobacco cigarettes and that this what is going to kill them when they're 25 and 30 years old.