Maybe he's referring to the suffering required to actually put the song together, from inspiration to pieces of structure to full structure to final polish.

Perhaps. I'm with you in your assessment, however.

These jazz folks didn't look they were suffering in doing this, but that doesn't mean their lives didn't have suffering before they gained acclaim and such incredible chops, or maybe they draw inspiration from the many people and cultures that have suffered:

https://www.youtube.com/watch?v=3pYHCGYJbw0

I'm also reminded of Stevie Ray Vaughan's dedication before he performed "Riviera Paradise" on Austin City Limits: "This one goes out to everyone who's still suffering in any way."

https://www.youtube.com/watch?v=3c_8VUL5jks

The beauty that was born from his suffering is certainly extraordinary, IMO, as is his song "Tick Tock", that he did with his brother Jimmy, in a message that should inspire us all on this day and going forward.

https://www.youtube.com/watch?v=N8uUTW9zPbM