We always try to do our dev work and connect to both the website and the app. In many (most) instances, though, in Latam going via web is the only way forward. That being said, we actively work with banks to partner up and establish direct connections too.
Partnering with banks you mean? Yeah, banks are slow to move but in Latam they're also pretty keen to partner up with fintechs if they see a win/win.
We work on the premise of end-users granting us permission to access and share the data they want for the means/apps they want. So there're an opt-in here. There's no general legal framework against this.