Hasn’t that always been the case though? Peer pressure is going to be directed somewhere, maybe cigarettes, maybe marijuana, maybe heroin, ... are kids really expected to be better these days than when we were kids?

Kids are better today than we were as kids. They drink less, they smoke less, they take drugs less often, they have fewer unplanned pregnancies, etc etc.

At the moment we don't think vaping turns non-smokers into smokers. But it's complicated, especially if there are companies that are marketing vaping to young non-smokers.

I personally think vaping is a useful public health measure, but I recognise the very many years of terrible behaviour from tobacco companies and it feels like light-touch regulation doesn't work.

to non-drugs?

Well balancing non-smokers becoming vapers relative to smokers becoming vapers definitely depends on the relative risks. But if vaping is increasing the number of smokers (which is definitely not true among adults, and probably not true among teens) you're right that wouldn't depend on relative risks.