[0] https://newsinhealth.nih.gov/2020/05/risks-vaping
[1] https://www.hopkinsmedicine.org/health/wellness-and-preventi...
[1]: "Vaping Is Less Harmful Than Smoking, but It’s Still Not Safe"
[1] has some problems. It seems to be conflating the vitamin E acetate issue with vaping in general. ("However, there has also been an outbreak of lung injuries and deaths associated with vaping. As of Jan. 21, 2020, the Centers for Disease Control and Prevention (CDC) confirmed 60 deaths in patients with e-cigarette, or vaping, product use associated lung injury (EVALI).") The section on "Research Suggests Vaping Is Bad for Your Heart and Lungs" focuses on nicotine. Which raises your blood pressure. And not much else, according to other sources.
I think the evidence is out as to what, if any, are the harms of vaping. But it’s not arguable that it’s better for you than smoking.
[0] https://www.newscientist.com/article/2120440-switching-from-...
I started smoking when I was 18 (2004), picked up some of the first vapes in 2009 (they were horrible), and finally stopped smoking in 2012. But I don’t want to stop vaping. I don’t like the modern mainstream ecigs like juul (I mix my own liquid and build my own coils on a dual 18650 battery device), but I’m just glad that vaping exists, because, if all my fruitless attempts at quitting were any indication, otherwise I’d still be smoking a pack a day.