That video is really confusing. It makes a few claims:
1. turning off onedrive backup deletes local files from your computer
2. there's no way delete files on onedrive without jumping through a bunch of hoops or losing your local copy
3. onedrive sucks because the file is only temporarily kept locally, and if for whatever reason it gets corrupted on microsoft servers, you're out of luck.
Is there confirmation for #1? That's really the only point that seems relevant to the claim of "onedrive just deleted my files", but I'm skeptical that onedrive is that bad, and the fact that he brought up the other two points (#2 specifically) makes me think what might have happened was that he deleted files on onedrive to free up space on his microsoft account, not knowing that it would also delete the local copy. The latter is still bad, but is at least somewhat defensible because that's how services like dropbox work. Also, if it's really #2, shouldn't the files be recoverable because onedrive has a recycle bin?