Addiction & Tolerance.
You choose to take bigger doses of Heroin more frequently instead of living a healthy life.
Your logic seems a bit too simple.
People have a tendency to push blame to external forces rather than take responsibility for their own actions. But personal responsibility cannot be the full story, because (almost) everyone acknowledges that drug addiction is something over which people have starkly reduced control.
So the question remains: What about other things "in the middle" like social media or porn "addiction"? Is it the fault of the person, the external force (which you must admit is consciously organised with the goal in mind of promoting the addictive behaviour, since their bottom line depends on it), or some mixture?