Do we have clear evidence for vaping causing harms of similar severity and frequency as smoking?

It's because people in general tend to learn and retain simplified versions of things. They hear that tobacco in cigarettes causes cancer but that candy-colored USB-charged devices can come without tobacco and completely miss the fact that nicotine is also a terrible substance to get hooked on. Even amphetamines are better because at least you can stop those whenever you want and all that happens is a few days of being sleepy and then you're fine. Try to stop nicotine cold turkey and, well...

its not directly education, but education influenced fashion. smoking became a blue collar habit in the west, and then no longer cool globally.