Our SharePoint was not really managed when we moved to Teams - we didn't use it (mostly because it's such a horrible product that has no clear vision behind it). But Teams started filling up stuff there all over the place.

In the end we did need to use it because we moved from another storage service to OneDrive (another "quick win") for a manager and OneDrive is really bad at team-owned storage, it's really for personally owned files only.