I'd feel a little better if every gun owning american had 20,000 rounds in their closet, than if they just had 20 rounds. It'll take time but supply will catch up. Those who were caught empty handed, well, shame on them. Hopefully everyone learned their lesson this time around.
I started stocking ammo 30 years ago when my grandpa told me how hard it was to find any 30-06 ammo during ww2. He had about 1/2 dozen rounds that had to last him several years. Couldn't find it anywhere at anyprice he said.
People should buy 2 rounds for every round they shoot. Sooner or later, one way or the other, supply will be restricted again. You can count on that. Don't have just enough for yourself, but your kids and grandkids too.
I don't begrudge anyone with enough forsight to buy as much ammo as they can. The free market works.