The music with a “Yiddishe taam” about which many peole love to reminisce was also influenced by the popular music of its day. Some of the most “hartzige” tunes actually turn out to have been composed by non-Jews.
It is not a coincidence that Sefardi music sounds so middle-eastern, and Ashkenazi music sounds so Eastern European. That today’s music sounds so American is par for the course. Don’t be such a fuddy duddy.