This move by Dropbox will reduce users' files to tiers: Rarely, regularly accessed data now kept separate

Not all documents are created, er, stored equal

Cloudy storage provider Dropbox has enhanced its bit barns with a tiered storage architecture that divides the contents of the platform into frequently accessed "warm" data and "cold" data, with the latter less likely to be disturbed.…

via The Register - Data Centre: Cloud
http://go.theregister.com/feed/www.theregister.co.uk/2019/05/07/dropbox_tiered_storage_architecture/