The upside to this decline in hi-fi owners (as dark as it sounds) is that there’s opportunity for the 55 and under crowd to pick up some sweet deals from the widows trying to unload all that "unsightly gear my husband left behind and I need to clear it out to remodel the room for my crafting studio. Everything must go!" posts on FB Marketplace.
I think about the decline of woodworking as a hobby in the States and how, if you keep an eye out for it, one can pick up some nice, barely-used quality hand planes, chisels, and the occasional vintage Delta cabinet table saws because neither the kids nor the wives of those woodworking hobbyists are remotely interested in keeping all those tools from the woodshop.