It’s interesting to see how technology or trends are dictating how the artists write songs. The past year's songs have been very long. The majority has been close or over four minutes. Sometimes even though the radio usually doesn’t take long songs people have released up to five to six minutes. Why you ask is it a trend? Not really it was that many believed that to keep the listener you needed to make a longer song. If they finally got in there and listened to your song, then you should keep them as long as possible. Also, short songs were always under scrutiny by Spotify.