Release artwork gets attention and profile art gets neglected — which is backwards, because your profile is what people see every time they look you up, not just during release week.
The pair is designed together so the banner doesn't fight the profile image, and every platform gets its own export rather than one file stretched to fit. Safe areas matter more than people realize here: a banner that looks right on desktop often crops the important part on mobile.
This isn't tied to a release, so it keeps working long after a single cycles out.