And yet, you are missing simple distinctions between authorization and authentication. You can authenticate with a separate identity provider. Every site that uses google login does that. They don't get access to your google account. You can also authorize specific things in your google account. Some apps do that too, and they get restricted access to a folder in google drive for example. Plaid doesn't follow any of these patterns. Instead, they show you a log in screen that looks like your bank's login (same colours and everything), only that you are sending your credentials to plaid. This is outright deception.