That's the thing, until this Open Banking stuff, I simply shared my bank account statements where I filtered out whatever I didn't want them to know - and I was sure that only few people in a local bank branch will see it, and the papers were disposed later.
Now I'm avoiding all this stuff like the plague. I'll never hand out access to my bank account through API to anyone. No inter-banking features or cool fintech apps for me, but oh well. My bank has good enough offer and the app is nice too.