Not really sure what you don’t understand. Yes, a credit card is a unique-enough

Not really sure what you don’t understand.
Yes, a credit card is a unique-enough ID that gives a direct connectoin between the user and the real person.
The primary purpose of this effort is to terminate the massive influence of bots.
Credit cards for bots becomes impossibly expensive.
So, this strategy solves that problem.
No one cares who you really are. (though they do check, if yuo are who you say you are)