> it keeps being true that you can just go to your bank's website and do whatever it is you want to do.
Not all banks. Monzo doesn't have banking through the website, and I doubt they're the only ones.
I just looked and apparently they do have a user API. It looks like it covers a lot of the functionality of the app.
That's true for personal accounts. Monzo business accounts can be managed through their website (with authentication via mobile device).