I wouldn't call myself a classical music fan, but if we're looking at Spotify stream numbers I wouldn't be surprised if a big chunk of classical is background noise too. Whenever I'm trying to get work done in a noisy environment I go for classical playlists - unless I'm doing something mindless like cleaning I find it very hard to focus with most music. Might just be that lyrics (especially in English) distract me, but classical is an easy go to for studying time IMO.