The original use of the phrase was in an old song, some version of which can prob. be found on the web.
It was just a melodic little ditty without apparent irony or cynicism. I’ll quote a few lines which I remember so you can try to find it at the end of my comments.
Then there is the reference to the Titanic which carries with it an aura of fortitude and courage even while facing death.
There wasn’t really much that they could do except offer what little comfort music could bring. One of the songs played was reportedly, “Nearer My God to Thee”
However, there was also a book detailing the early history of the AIDS crisis by Randy Shilts entitled “And The Band Played On”
In this case there is a far more sinister use of that phrase as it became clear that there was a lot of denial and delay in funding by bureaucrats trying to keep a lid on it.
So the metaphorical slant is pretense in the face of devastation.
This was not the case on the Titanic because everyone was soon aware of the inevitable doom awaiting so it wasn’t as if the band could cover it up.
But with the AIDS crisis, that was the case in terms of the govt. Many lives could have been spared had there been prompt notification to hemophiliacs once there was the realization that blood was definitely one of the routes for transmission.
Reagan never uttered the word AIDS. C. Everett Koop tried to stress how important condoms could be in mitigating transmission but no one in govt. wanted to hear it.
Those are just a few examples of why Randy Shilts chose that phrase as the title of his book. He was clearly p*ssed off about all of what his research turned up.
If you study the lyrics of the song you quoted, you will see that the phrase is being used in a similar manner as Shilts did except that this time around the band played on is distracting from and disguising the dangers of possible nuclear holocaust (according to the viewpoint of the song’s author)
“And the band played on
Driving me to distraction
As the world came crashing
down around us.”
So that’s basically my take on it and why I think it has more to do with the rationale behind Shilts’ using the same phrase to title his book. The song seems to be saying the same about the bands playing in order to distract from nuclear holocaust in the same manner of ignoring the AIDS crisis in it’s early stages.