It's not about pretending they're healthy, it's about not pretending like they're anywhere near as terrible as smoking tobacco, which is terrible. The argument

It's not about pretending they're healthy, it's about not pretending like they're anywhere near as terrible as smoking tobacco, which is terrible. The argument seems to be "they both involve inhaling and exhaling something that isn't air, so they're both equally bad." Personally I think it's mainly to do with the optics of it. As a society we've spent all kinds of money and effort to stop smoking, and it's now heavily stigmatized. So to see something come around that appears similar to smoking seems to drive a lot of people nuts.