Well with other currencies you sort of have a nation state behind it, backing its value. Failing that, that nations armed services :-)

I don’t get crypto… is there any coin that’s actually usable as, you know, currency?

From what I can gather, none of them scale so each transaction is slooooow and expensive.

The coins themselves carry no value and is backed by jack-shit. Comparing them to baseball cards seems very apt. Baseball cards, bubbles and FOMO.