[namaria]

> Credit cards don't directly send funds from point A to point B either

But dollars change hands (or accounts) at the end.

> using a debit card from your bank to purchase something doesn't count as buying something with USD because the paper notes you deposited at your local branch aren't the same physical notes that the merchant pulls out of their bank account.

Nobody made that argument. You did and argued against it.

> which is that you can deposit cryptocurrency and spend it

You buy and sell cryptocurrency so you can use the currency you started with. The added two steps of buying and selling crypto are immaterial to buying what you want. You merely invested and divested in a speculative asset, you didn't use it as currency.