But in this context, is it so important to distinguish between whether something is physiologically addictive vs. just seriously habit-forming? Except for substances where withdrawal is genuinely life-threatening, the practical difference seems to be in degree, not kind. Nicotine withdrawal causes irritability, but (I know having experienced both) so can breaking a bad social media habit.

(And it seems like there's a physiological basis to both cases, it's just that one involves endogenous chemicals and the other doesn't)