It is physically addictive. Research has shown this already I am fairly sure. It's not nearly as addictive as some other things like alcohol obviously. Psychological addiction also shouldn't be dismissed.

Sugar is dangerous? Maybe refined sugars are - especially if you're diabetic - but most sugars are actually natural and some form complex carbohydrates and fibres. It's a lot more complex than this hot take. Sometimes even diabetic people need sugar in an emergency condition called hypoglycemia. It's also not in any way a drug; really wish people stopped saying this. Also genetic material is partially made from sugars like ribose and deoxyribose.

There are real life consequences to smoking too much weed and this can include damage to your lungs and can negatively impact the brain. Brain problems is mostly an issue for people under 25 though so smoking after this age is less problematic. That being said it's still much better than some other drugs like you say. Before people ask yes this includes alcohol as alcohol is quite toxic to brain and body when consumed habitually.

Weed can't replace all prescriptions either. It's just not as good at blocking pain as opiates even if it's a lot safer. That being said if it helps you then that's great - especially if it's in edible form or spray form as this is healthier than smoking.