It boils down to an obvious disparity in the standard of proof they demand for "pet" topics versus what they need for everything else. You can do this kind of ultra-nitpicky "rational inquiry" to undermine anything you don't like. You can use it to argue against seatbelts. Or against the ban on lead paint. Was lead paint really all that bad?... and I mean, really? Are there studies? Are they high quality enough?... Double-blind? Confounding factors? Correlation or causation? Even if they look solid, I bet they contain enough errors to cast doubt. Cui bono? What was the role of the titanium dioxide lobby in all this?

For nicotine specifically, I've been around enough people seriously addicted to nicotine to just roll my eyes at this stuff. I had things thrown at me by a visibly jittery relative when I refused to smuggle cigarettes into a hospital. Do I have a published double-blind study showing that it's worse than coffee? No. But again, neither do rationalists for 99% of the stuff they believe in.

Do I think that vapes are a noteworthy problem to be focusing on? Maybe not, but public policy is always to some extent vibe-based. And the harm of being too heavy-handed on vapes is really not something that keeps me up at night.