This sense of play hit home for me when I was a late teen and bought a 4-track multitrack recorder in the mid-80's. I had no preconceived notion of a song I wanted to write/record. I simply plugged in my guitar and hit 'record' and laid down an idea. I may have had a few false starts but didn't sweat it. By itself it wasn't very interesting. I added a second track with the only goal of "it should work with the first track" and was surprised at how easy it was to achieve that goal. Suddenly, with the two tracks an idea began to emerge that wasn't present in the first track by itself. Rinse and repeat with the remaining 2 tracks and I had a musical idea that I never could've imagined I would have created.
I still use that same method to generate ideas today, and summon that same sense of 'play'. Of course the real work, much harder than creating, imo, is editing.