I think that this was most influenced not even by the banal desire "to be cooler and more mature" and the craving for new sensations, knowledge, etc., but by the romanticization of drug addiction and its force on social networks (and usually this is precisely the emphasis on aesthetics of use, not sensations), as well as a massive fascination with the culture of raves, which have always implied the use of illegal substances. Another possible factor is to get substances, especially for underage adolescents, much easier than alcohol. Recently, drugs among teenagers have become not just a fashion but a kind of must-have, something common and far from forbidden. Even those who try it for the first time no longer feel special and are not afraid that their peers will not understand them.
Modern adolescents who consider themselves educated (most often the prefix "pseudo" is appropriate here) people have a fashion for self-knowledge and art. Here drugs act as an auxiliary handout. I will cite as an example artistic creations that reflect the state of a person during drug intoxication. I can say the same about writers.
Unfortunately, the majority who use it solely for the thrill of all sorts of Vicugan parties and raves are left behind.
Substances are a little unusual, non-standard thing for society. To try them, you need to have some openness to everything new, curiosity that is characteristic of young people. For example, there is a certain grandfather. His whole body hurts, he has poor appetite. He would smoke ganja every day, and it would hurt less, and would eat better, and the mood would be upbeat, would not grumble so much. But he cannot - at the wrong age to try something new, this kind of upbringing, character and conservatism typical of age. But young people - for them, that jumping off a bridge with a bungee, that without money to go to Europe for a month, that to try something new is essentially one thing.
I tried to analyze the origins of the addictions of the younger generation somewhere here, so I'll just add the nuances of the topic of drugs.
Drugs for adolescents are a spherical "forbidden fruit" in a vacuum. Even their parents do not use them, so such experiments make it possible to look not only "more mature", but "more dangerous", "riskier" and, accordingly, cooler. All this is greatly reinforced by media culture, because "vile death from drugs" can only be seen in homegrown documentaries, but the protagonist-drug addict is a frequent topic in both feature films and music, and the media personalities themselves do not disdain, as we all know.
The second is, of course, the Internet. He not only promotes and imposes this kind of thrill, but also convinces children that life itself is joyless, empty and meaningless, so why not shorten it, at the same time diversifying it with fabulous "parishes".
Well, there is no point in arguing that drug use brings people together. All these "entries" are a kind of analogue of "group interaction", which children do not receive due to their detachment from the outside world and their natural environment - peers, classmates, like-minded people.