An adult should be able to do whatever the fuck they want, as long as it doesn't impact other people. Vaping doesn't emit any carcinogens or toxic substances, and 10 times less nicotine than smoking does. At the end of the day, vaping does far less harm than smoking, and it's easier to reduce the amount of nicotine consumed with vaping. Nicotine also has health benefits, such as slowing down the onset of Parkinson's.
If teenagers are vaping then that's an enforcement issue, but at the same time I would be less worried if I found a vape in my kid's bedroom than a packet of cigarettes. Teenagers will experiement with substances. Nicotne vapes are way down the list of ones I would be worried about.
Saying that vapes are dangerous is misinformation at best. Vaping got you off smoking cigarettes (congrats btw), which are far more dangerous. Yes, you may have consumed more nicotine, but you didn't consume any of the other thousands of toxic or even carcinogenic chemicals present in cigarette smoke.