If your passport leaks, they can [create a bank account]
This seems like a country-specific problem. In Japan, even if opening an online bank account, a photocopy of a passport is simply insufficient to pass identity verification. Additionally, most country passports contain an IC chip that can be used for attestation. Any eKYC system that does not attempt reading data from the IC chip is fundamentally broken.
It should be a total non-issue for photocopies of passports to get leaked.
Those people are not going into the bank with photocopies of passports, they are creating fake passports for that, all they need from the photocopy is the number to put in the fake one.
And in many countries this days you can create a bank accounts using the bank app and all they ask for is a photo of your ID/Passport, now you dont even have to create a good fake for that.
It should be a total non-issue for photocopies of passports to get leaked.