> It hands over the customer's IBAN, which isn't really that much safer than a credit card number, since any merchant can trigger a SEPA Direct Debit using it.

Yes. And they would quickly lose their ability to process any payments. This is the exact same idea as how credit cards work. I don't see my IBAN as a secret, all my friends have it, as thats how they can send me money right to my account.

> that requires you to actively monitor for fraudulent transactions, which a decent system wouldn't allow in the first place.

So that rules out credit cards too, exact same system.

I'm not familiar with pix mentioned in the other threads, but I am not familiar with any other system that is better