German Netflix series fact check: use of acid/party drugs among late 20s early 30s in cities?

I’m an American watching the 2024 sci-fi series Das Signal on Netflix (English subtitles) and there’s a scene that shows a flashback. The flashback is being experienced by a 40something male thinking back to him and his now wife as a late 20’s/early 30’s male/female couple having a date in a carnival funhouse. I’m not German but it’s obviously an urban scene and it looks like Berlin to me rather than one of the other large cities. At the start of the scene we see the woman put a square tab in her mouth and show it to the man before, ostensibly, swallowing it. For context, she is clearly more of a city type person than her partner.

My feeling is that I am missing out on the filmmaker’s intended context. I’m wondering whether this is a local shorthand for a type of person or experience. My question is: what do we think the filmmaker was portraying? Is it a city/country divide? Is it about the different ways a girlfriend and a wife may behave?