When using a government website, you were intimidated by the security posture of... Plaid? (Genuine question, maybe this was some other provider but Plaid's aggregator tool is the most common place I see this pop up in real life for ACH)
It also seems to go against common security advice. "Never log into your back account if redirected by a website you sort of, but don't really trust, except sometimes its alright and it's up to you to tell the difference" is a terrible way to secure banking.