Well, I'm looking at all this from different angle.
First time I heard this song my first thought was "well, this could've been in 1st esc just as well". Seriously, that really was my first thought
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And that really is so, this song really does sound like the ones 50, 60 years ago.
Esc isn't only about the music. It's also politics and general sociology. Nothing ever happens here simply "by chance".
During history, music styles have changed through centuries and every time with some bigger point behind it. Now we're faster and it works in decades, even years.
The question is: why did european audience go for something extremly classic and simple and basically timeless? Something that might as well have been in 1st esc?