Even if they completely screwed up all the security in a way that would never pass compliance testing broadcasting all card info for every transaction to the ne

Even if they completely screwed up all the security in a way that would never pass compliance testing broadcasting all card info for every transaction to the network in the clear, with EMV cards all you’d get are EMV tags that are useless for anything but taking that one payment on that one terminal at that one time for that one amount. You couldn’t use anything you harvest to make a new transaction on the cards, or even replay the transactions you saw. (Mag-stripe is different, don’t use that!)