no.

neither social media nor smartphones are; the control of major social media by multinational corporations, in service of the US government, is. That's what optimizes them for engagement, that's what controls, blocks, throttles, and censors content to fit US government and multinational corporation interests and that's what nudges users to silly dance videos as a way to draw attention away from everyhing that's going on.

Like with actual drugs, the governments may say that they have to "regulate and control" them to "save the children", but that's been facade in both; the US government has been the world's largest drug dealer and a major partner in drug cartels worldwide. (just as a case in point, decades of "trying to control the poppy growth in Afghanistan" were "unsuccesful" while the US controled it, while after US retreat the production plummeted to almost nothing). The US is also the largest social media sedation dealer.

(It doesn't 100% work; the decentral upload, a core of the business model, stuff that's not sedative still gets through, which is why they're all scremaing for censorship and control now; because as horrible as the algorithms are, stuff still gets through).

Social media isn't a problem per se. With more social media like SN and nostr, and more corporate social media suicide through overt censorship and users fleeing, you'll see the induced adhd decline.