I'm actually quite experienced with web scraping, mostly using PHP and XPath, but also with Javascript as well as a custom approach written in Rust. I know in detail what an inconsistent mess everything is.

That's why I'm so uncomfortable handling things like bank transfers over such inconsistent, buggy systems, which is what Plaid does. It's not read-only: https://plaid.com/use-cases/consumer-payments/

Not to say I don't trust Plaid, I'm sure they're aware of all this and very careful about how they do things.