How do credit/debit cards satisfy the proposition of a decentralized marketplace?
They're something that most people are actually using, allowing the marketplace to actually conduct commerce and exist.
And again, how do credit/debit cards—which are centralized systems—satisfy the proposition of a decentralized market?
"And again, how do credit/debit cards—which are centralized systems—satisfy the proposition of a decentralized market?"
They allow the market to actually exist, by using something that the people are actually using.
But a decentralized market does exist with cryptocurrencies.
And credit/debit cards aren’t decentralized.
Clearly not for the people using it right now.
What benefit does this actually give me in my everyday life where I don’t need to buy toilet paper anonymously?
Are you asking why someone would want to transact anonymously?