Suppression: when we suppress emails, it doesn't alter the marketing consent status on any of these profiles. It simply means that you've chosen not to email these customers, for the time being. You can always email them later. It's a clean method of segmenting profiles you prefer not to message.
Opting out: If someone unsubscribes or marks you as spam, they are permanently removed from your email pool, and we don't interact with them at all.