While it’s incorrect to say the dangers are equal the dangers are greater for developing brains than adult ones. Nicotine is a vasoconstrictor. It makes blood vessels smaller.
I personally think the juul is a less than ethical device. Not only does it follow the razor blade model, but it has a grotesquely high nicotine content with no path to reduction. It is designed to addict. Little wonder they were bought out by big tobacco. Dung attracts flies after all.
I am annoyed by the generalization of e-cigarettes in this instance. The juul is an exceptional device, not the rule.
JUUL hasn't been bought by a tobacco company.