I'm a new 22.4, so I'm gone. But the Spanish flu didn't have an outsize impact on the economy either during or afterwards. Not the same situation here, but something to consider.
One thing I think might happen, though, is not that most businesses close forever, but that they realize from all this that making everyone telework or buy online is a LOT lower overhead, with a lot of companies closing storefronts and offices, but staying in business. That may be better for us (or you, since I guess I'm getting laid off) overall.