It's better than smoking, but we need to be responsible and admit that it's not exactly without risk or harm.
https://pubmed.ncbi.nlm.nih.gov/30049223/
> Conclusions: Single-dose inhalation of vaporized cannabis had no clinically meaningful positive or negative effect on airway function, exertional breathlessness, and exercise endurance in adults with advanced COPD. Clinical trial registered with www.clinicaltrials.gov (NCT03060993).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4456813/
> The majority of studies suggest that vapourizers adequately reduce risk of pulmonary symptoms (5,14–16), although complete safety may require a regulated source of plant material, rather than ‘street’ samples, which produce ammonia (17).
> The findings suggest that vapourization reduces the delivery of toxic byproducts associated with the use of smoked cannabis. A subsequent experiment addressed exhaled carbon monoxide (CO) (14). The researchers found a statistically significant difference between the increase in CO exhaled following smoking cannabis versus vapourization. The amount of exhaled CO showed little to no increase following vapourization compared with large increases following smoking, which would be expected for inhalation of a combustion product. These findings give further evidence that vapourization reduces exposure to gaseous combustion toxins.
This isn't to say there is no risk, but if someone is going to consume cannabis it is amazingly clear that vaporizing it is safer than smoking it.
In most cases? Where in the world? In Canada at least, frequent cannabis smokers and frequent cigarette smokers are nearly disjoint groups.