A smart phone is a human right, according to you? Of course you can ban them. The addicts will have to wean off, but after that, there's no disadvantage.
Technology is in most of the cases not bad, and their use can enrich lives.
For example, in many countries that legalized Marijuana the number of addicts did not significantly rose. Further the police now have even less to do, as they do not need to control these people if they are taking this drug.
Furthermore, the supply chain isn't comparable to drugs: you cannot illegally import facebook, and you cannot make a ton of money out of it.
And legalization, i.e. the status quo, just keeps the problems too.
It's a bad metaphor.
BTW, I explicitly mentioned fentanyl. It is regulated. And we all know what happens when you release it for free. Now that I think about it, you didn't reply to the argument at all. You just mention war on drugs, then shift to marijuana in a kind of gotcha style and hope no-one notices.
<tangent>And then we look at AI and think "surely this time it will be different"</tangent>