>> What I don't understand about the crypto remittances argument is how the people sending and receiving them are supposed to convert them into spendable currency.

For all the harsh words you posted without evidence, thankfully you've at least admitted you don't understand much.

Your premise is that cryptocurrency is not "spendable currency" which is simply false. I pay people in hyperinflationary environments in cryptocurrency variants with low transaction costs and fast speed, and they in turn directly spend it on physical goods like food.