I think for this you kind of need to sort the white girl music into late 2000s/early 2010s, late 2010s (post 2015) and 2020s pop songs/artists, because white girl music/pop music changes so much across these three timeframes. If I had to do all three, then I would probably choose 1 from each era of pop music. However, I haven't listened to enough post covid or late 2010s white girl music to give a fully informed big three. My big three would probably be from the early 2010s pop music era, but the issue is so many pop artists dropped a couple of bangers before vanishing off the map, so I can't really say my big three because they didn't really own the pop genre with multiple albums of iconic pop music. Having said that, Katy perry is definitely on my big three. I also love Rihanna because she has so many bangers that i love. My last choice would be Sia, because not only has she dropped some absolute bangers, she has also written songs for half the pop industry, including all of your favourite pop artists.
There are so many other great white girl music artists that I can't name them all though.
Tldr; can't really speak for white girl music across the whole time frame, and lots of artists who only dropped a couple of really popular songs so wouldnt make my big three. Big three: Katy perry, Rihanna, sia
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