Well you really missed the entire point of the show and summed up your ignorance of it pretty aptly.
It's about way more than your surface observation. If you've been through addiction then it's probably a show that will really resonate with you. The aim is not to watch adults pretend to be teens, it's to watch people you can sympathize with, go through an incredibly difficult age and deal with a collection of problems that you've had before. If you've been through drug culture and made it out the otherside, you will recognize a lot of the characters as people you've known, or been.
You're right that I haven't watched it and know nothing about it, but I'm far from the only one since literally all I've heard about it is Sydney Sweeney's tits are out in it.
I get where you're coming from, but the reason I like it so much is it addresses so many issues I've had to deal with, or know people who've had to deal with them. The way the main character describes depression and anxiety, the way they keep trying to be better but ultimately repeat the same mistakes when things get bad, it makes me feel like someone finally understands what I'm going through, which is comforting. There are a ton of other heavy topics addressed, like drug abuse, anger management, gender identity, sexual orientation, and more, and I felt like it was done in a really good and non-judgemental way, where it wasn't like the writers were trying to tell you some "moral of the story" but instead just acknowledging these are real world problems and that life is really hard.
It's kind of painful to watch for me with how insufferable most of the characters are and how terrible of decisions they constantly make. Still has plenty of good parts, and sadly Fez was probably the best part of the show for me
As the article mentions Euphoria is a HBO series starring among others Zendaya. Apparently according to Wikipedia it actually is HBOs 4th most watched show (behind Game of Thrones, House of the Dragon and the last of us).
I couldn't tell you much about it since I haven't watched it, but it's definitely not an obscure show.
It took me by surprise when someone mentioned it and I had never heard of it, despite liking some of the actors and HBO stuff in general. Maybe because I'm not US based, perhaps? I started the show a couple of months ago and it's worth a shot.