Oh come on, ABBA was probably the most global phenomenon ever coming out of Europe. Everybody is an ABBA fan, even if they haven't discovered it yet ;)
I’m in my late 30s and have never understood the Abba obsession. I’ve heard some of their music and it doesn’t really do it for me. And the weird way everyone acts about Abba, like you see in this thread, just reinforces that for me.
It's probably at least partly a 'you had to be there' situation to remember how popular, globally, that band was back in the 70's. The fact that they weren't from the US or UK made them stand out even more.