This reading doesn’t make sense. There’s no way to extrapolate from this to any statement about 40% of the population, and even 40% of the day is a serious misread imo.
> it would imply a massive epidemic of THC overuse.
Not really, due to THC content in the body not being a reliable indicator of impairment or even time since use.
If BAC were more like THC levels, I suspect the data would show 40% or more of the population has consumed alcohol - or, in your words, is drunk "at any given moment"