Congrats on the launch! I'm the CEO and co-founder of https://teller.io that uses private mobile banking APIs to provide access to bank accounts too, and you're right it's the way to go. We don't think regulation or OAuth based APIs will ever yield an improvement on this approach (explained why here - https://blog.teller.io/2021/06/21/our-mission.html)
You're going to quickly find out that these API endpoints are commonly very well protected as build out your coverage however!
You're going to quickly find out that these API endpoints are commonly very well protected as build out your coverage however!