- A single bitcoin "transaction" can actually have thousands of inputs and thousands of outputs. So energy "per transaction" or "transactions per second" is not analogous to a typical monetary transaction.
- Bitcoin does not compete with literal credit card transactions (although some use it like that today). I'd compare Bitcoin on-chain transactions with how nation-states settle their central-bank ledgers with gold. Gold is the best comparison to Bitcoin because trading in hard gold is "final". Credit card transactions happen on a higher level in the financial stack. As does cash. As do bank transfers. All of these bubble down into interbank transfers that eventually settle on the base layer of central banks. So compared to shipping and securing gold, Bitcoin is quite cheap!
- Adding to the above point; if Bitcoin succeeds in beind "adopted", it would not mean we no longer use credit cards. Credit cards would just port their underlying mechanism on top of Bitcoin instead of fiat moneys.