In fact, the primary band program at my high school seemingly only existed to fulfill this role. I ultimately dropped it because I was sick of doing unpaid work

In fact, the primary band program at my high school seemingly only existed to fulfill this role. I ultimately dropped it because I was sick of doing unpaid work for the football program outside school hours. I'm pretty sure the extreme emphasis on marching-compatible instruments in high school music programs is entirely due to this, in fact. I wonder how many 17-year-olds play the tuba or trombone or clarinet in Europe, versus the US, for instance? In an ideal world I'd see all non-specialist students at that level learning piano/keyboard, or maybe guitar or ukulele. Something with good general utility, acceptable when played solo even at not-great skill levels, and relatively easy to reach a point where you can lead a sing-along. Nice, physical, evident mapping of notes and theory to the instrument, too, unlike wind and brass instruments.