Microsoft indicate Storage Sense is not enabled by default in Windows.
Storage Sense is basically the same as Disk Cleanup that runs on a schedule, but it also will clear out the Downloads folder and also OneDrive local cache for files not used in a while, it will only delete data if your drive is short on space to ensure Windows can run efficiently.
Automatic Maintenance has nothing to do with storage on your drive, it is run on a schedule to perform tasks like installing updates, running diagnostic system scans and security scans, and also optimizing disks (file system) on your PC.