The standard unsubscribe link in Pardot is a one-click unsubscribe link, meaning that once the link in the email is clicked, the prospect is unsubscribed automatically. While this makes it easy for the prospect to opt-out of your emails, it also makes it easy for spam filters to click this link and unsubscribe your prospect unintentionally. Unfortunately, there’s no way to customize the standard unsubscribe page to prevent this from happening, but you can create a preferences page and customize it to act like an unsubscribe page.