There is no reason to assume that a behavior that activates the reward system is categorically less harmful than a molecule that activates it directly. In both cases it can completely overcome someones will such that it destroys their life and they can’t escape it. Both are addiction. You’re making a distinction without a difference- a fire only needs to be hot enough to kill, it does not become “invalid” just because you can think of other types of fire, or hotter fires.
You are using the word “medical” to emphasize your point incorrectly- behavioral addictions are included in the modern medical concept of addiction, and the idea that they should be considered categorically separate from substances is an outdated concept. The DSM-5 for example has a diagnostic criteria for gambling addiction.
>no reason to assume that a behavior that activates the reward system is categorically less harmful than a molecule that activates it directly.
There are mountains of papers, books and all sorts of evidence that drugs that directly act as agonists for populations of dopaminergic neurons the VTA that mediate incentive salience (methamphetamine, cocaine, etc) are incredibly addictive (wanting, not liking, not reward. reward prediction). This is very different than an experience that is naturally rewarding like sex (liking, and maybe wanting later remembering the liking). Anticipation of sex may activate VTA dopaminergic populations but the reward of sexual activity itself does not. And certainly not things like viewing audio-visual media on screens.
I use medical to emphasize that when you try to reason about these things without fine grained understanding you come to false general conclusions.
I do agree that with drugs that just activate reward directly (like opioids with glutamergic populations in the shell of the nucleus accumbens) can rapidly become addictive. But these too are different than expriences that happen to activate reward through sensation. For example, sexual activity is a behavior that activates reward yet very few people become addicted to it.
You are using the word “medical” to emphasize your point incorrectly- behavioral addictions are included in the modern medical concept of addiction, and the idea that they should be considered categorically separate from substances is an outdated concept. The DSM-5 for example has a diagnostic criteria for gambling addiction.