Also in Argentina. Lots of social clubs and vecinal associations that offer this. Maybe what op is talking about is a US thing?

Even in US, I would imagine stuff like Salsa, Westcoast Swing, among others, are relatively common.

They absolutely are.

Any city will have ballroom, swing, salsa, tango, etc...

Even in rural areas you will find line dancing.

This is aside from informal dancing at bars and clubs which exists in every place I've ever lived in (6 countries in the Americas so far)

Those genres of music/dance require you to actually learn how to do them properly. The music is also not very popular. Personally I love listening to your two examples, but my point stands.

Maybe it stands in US, not in the European places fully crowded I occasionally visit.