If anyone who can look at this chart he did and think he's anything other than a fart sniffing academic quack , I can't help you
Butane, which can just kill you randomly, less dangerous than other drugs to the user?
At some point benzos were involved in something absurd like half the murders in Scotland, but they're less dangerous to others than tobacco?
I'd guess that he didn't take into account the amount of people actually using each drug when making the chart, but surely that's a pretty basically thing that should be taken into account?
There was a drug impurity included in some synthetic opioid in the 1970s that gave you permanent parkinsons if you took it once, is that less dangerous than alcohol because nobody in the UK uses it?
Also the "Ecstasy is less dangerous than riding a horse" thing was always moronic. In chances of dying, maybe,
but riding a horse is not neurotoxic like use of MDMA is.