I don't think that band will go. Those that decide to try and innovate and adapt to the new conditions will flourish, while those who try to cling to the "old way" of doing things will be in for a rough go of it.
Things have gotten uglier in this country before (Kent St?) and we have seen disruptions to life before (WW2). While I'll readily admit those aren't one-to-one comparisons, my point remains: the act of collaborative music-making will survive.
Just like military marching has (largely) become a part of our history (no offense meant), so will some things that we used to do pre-COVID.
Maybe this is the end of the mega-spending on marching band and the emergence of chamber music as the centerpiece of band programs? That's just one of a huge number of possibilities. In any case, I'm not sure that's such a bad future...