> "Did men and women stop making babies and I didn't notice?"

In the US, birth rates have declined from ~2.0 children per woman in the 90s and 00s to ~1.6 in the 20s, so yes.

Also note that your numbers seem to be single or not single rather than married or not married — that is, folks who are dating are included.

I will also add that there are people in my social circle who are very much in FWB relationships or “situationships” — that is, it doesn’t seem like a nurturing, consistent, or stable relationship from the outside looking in. These folks probably don't count as “single” in your numbers, but they functionally are.

As for folks over 50 — yeah, I’ve seen a lot of them just give up on dating. They live very active lives, and dating isn’t a part of it.