Early 30s, sure. Late 30s and 40s? You should qualify your statement with “this is a heated historical debate, but some people argue that…” Keep in mind the significant incentives to not seek out information, to disbelieve the information one did come across, and to lie after the war was over.

One of my neighbors when I grew up was part of Hitler Youth, and had moved to the US after the war. (for time context, I'm in my mid 30s, and he died a decade ago at IIRC 95 or 96, and I asked him about it maybe 20 years ago.)

I asked him if he and his fellow youths knew of anything. He said at first, no, but pretty quickly when all the jewish-owned businesses vanished almost overnight, everyone knew something was up. Did they know about the camps? Debatable. But even the kids knew that they jewish population was kicked out of society.

They definitely knew something was up. There were active roundups of victims and a staunch public policy of ghettos etc.

Laughably false, camps like Dachau were on newspapers and newsreels. Almost every Germans were aware that they were rounding up Jews and murdering them in camps.