Most fans now opt for "offline listening" through subscription services. While these aren't traditional MP3s you can move between devices, they allow you to download the music for listening without an internet connection.
For those interested in downloading The Beatles' greatest hits as MP3s, you can find their songs on various digital music platforms. Services like Spotify, Apple Music, and Google Play Music offer a vast library of songs, including The Beatles' discography. beatles greatest hits mp3 download