As a boozer and a dope-smoker, I agree that alcohol is far more dangerous than cannabis.
In fact I was mightily relieved when my son moved from being a trainee lush - when he was constantly falling over, getting into fights and even being carted home by the rozzers - into a pot-head. OK, the fridge maybe needs a padlock now, but the anticosial and self-destructive side has gone.
However - and there's always a but - dope isn't completely without its problems (and I speak as someone who's maybe smoked four days a week for a quarter of a century). Too much too often can sap motivation and turn you into a sad, boring git who can't be arsed to get up and go out to work or contribute sensibly to society.
That said, booze is far more damaging.