Gambling is conventionally considered addictive, but the user isn't ingesting chemicals. I don't think a physical/non-physical binary really stands up under scrutiny. I mean, aren't all addictions physical insofar as they stimulate the body to produce neurotransmitters?

Plus, smoking doesn't kill people; its pathological outcomes do. Similarly, looking at a phone screen might hurt a user's eyes, but it won't kill them; however, the decisions that user makes over time due to the effects of the subject matter they interact with might definitely put them at risk. And if aspects of that subject matter are deliberately amplified for their addictive properties, should platforms be regulated to control this?