Today at my corporate gym, the clueless gym managers play (off a satelite) some truly annoying trash called techno or 'house', that I myself call modern halfass disco. Something to offend some. Whereas easy listening was something to soothe all, even if it didn't always succeed, with us Jimi Hendrix fans.
They were hugely popular on top 40 R&R stations in the early to mid 60s. Teenagers loved and appreciated the change of pace.