FWIW, I'm very familiar with Plaid as I've worked in several FinTech startups using Plaid for various reasons. If you simply want to revoke Plaid's access all you need to do is change your bank password. Of course, all past data will live on in Plaid. If you're a EU user, you can request to have your data removed. Curious what their response might be if you're not in the EU. Hate to be cynical, but I bet they'll ignore you as is all too common for customer service these days.