In order for Stripe to maintain these standards, they require various information from anyone creating a Stripe account. That may require a government-issued photo ID and/or SIN or Social Security Number. Stripe is required by law to complete what's called a KYC (Know Your Customer) survey for every business that signs up with them, regardless of how many transactions they've processed. This involves completing in-depth reviews of every single business, including what's being sold, the intent of how it's to be sold, a description of the products and services, the website, and identity verification for the person who chooses to be the owner, administrator, and representative of the Stripe account. You can read more about this here: https://support.stripe.com/questions/why-do-you-need-my-date-of-birth-and-4-digits-of-my-social-security-number
When setting up your bank account connection, please refer to these requirements to verify what information you'll need.
As per Stripe's privacy and security, personal information is only used to complete the KYC. You can read more about their security and privacy in the links below: