The "gateway" thing is funny. To many vaping outsiders, e-cigs are a "gateway" to tobacco use. To almost anyone who vapes, e-cigs are a "gateway" to quitting smoking.
This isn't news to me. 95% of the people I know vaping are ex-smokers. About half will not be giving up nicotine any time soon. Vaping is a risk management approach. Glad to see it in publication for the general public.
My risk management choice using vaping over smoking is in direct conflict with America's public health's goals.