I think, people are reading too much into Gaeta singing it like they did with the watchtower song. It's a song with some meaning behind it but the fact that Gaeta is singing it doesn't mean diddly. It's just directorial wallpaper that Ron's known to favour because he likes pushes boundaries and letting people show their stuff. Personally, I wanted to belt Gaeta's head into a bloody mess of pulp and splintered bone when it dragged on but I appreciate it was a neat gesture. But, yeah. I agree it means something. What? Dunno. Maybe it's just enough to be an attention hook and give something people to tak about, if you want to get cynical.