Yeah, they split them out. Wallet is your Google balance and you can use it to pay people or buy things in Play. AP is just for paying for 'stuff', with your linked bank or cc. You can fund your wallet but not AP, that never has a balance, it's purely for paying (not people) at stores etc.
Some cards do still work, if they were added in Wallet way back when they will continue to work in AP. But, now, if the bank isn't participating you can't add it. My sister still has a card that she can use from her credit union but they don't participate (yet) with AP so her neighbor can't add her card.