It helped me quit my decade-plus long smoking habit, and I'm now 3+ years off of vaping as well. I hate to see vaping demonized, but I also don't particularly care to see kids take it up. It's just as, if not more addictive than cigarettes.
We could use even stricter rules (such as making vapes prescription products) to tilt it even more towards the "quitting" market.
Good thing we don't have to worry about it because it's a situation we have data on. You've created a hypothetical that is incorrect. Before vaping cigarette use from people who had never smoked before had plummeted to almost nothing. Meanwhile, 1 in 4 kids from 6-12 grade vapes.
Vaping does not generate dangerous particles in the form of second hand smoke — on the contrary, second hand tobacco smoke is around 95% as dangerous as smoking yourself.
I don't know of a single person using it as a cessation device. Anecdotal, of course, but still, didn't expect such big of a difference compared to your post.
I think, (barring dangerous additives like the buttered popcorn flavorings), that vaping is probably 3-10% as harmful as smoking. Not harmless, but less harmful, if that makes sense.
The older generation, those who were adults in 2010 or thereabouts, all used to smoke. We rapidly adopted vaping for QoL improvements: No more smelling like an ashtray, massively less costs, improved lung capacity, and as a side affect, quitting became massively easier.
Every cigarette user I know that switched to vaping has in turn found it easy to taper nicotine and quit. Vaping doesn't have the same addictive power as cigarettes. I was a 10 year smoker with multiple failed attempts at quitting, vaped for two years, then just stopped.
As for popcorn lung, this was widely known and discussed within the vaping community at the time, basically within a year you could not even purchase the affected flavorings without being very intentional.