If I have a synced folder with files: 1, 2, 3, 4, 5
And I edit/change file 1.
And then I delete files 4 & 5
And then add 6, 7, 8, 9 & 10
Most cloud storage software will upload the new version of file 1, delete files 4 & 5 from the Cloud folder, and upload 6-10. Files 2 & 3 are unchanged, so there's no reason to waste time re-uploading them.
Expand the process out for 150 files.
Cloud storage providers that offer snapshots, or which are geared towards backup and not just actively synced storage, will keep the older version of File 1, as well as Files 4 & 5. But you have to know how to go through the file history.