I too have a problem with Google Drive storage in that all my photos have been automatically uploaded to Google Drive at full size taking up almost 100% of my 15GB storage quota.
It is possible to remedy this by:
- Deleting all the photo files from Google Drive;
- Then adjust the computer settings so that photo files are in future uploaded at standard size only;
- Then re-upload all photo folders/files manually which on this second time round will be uploaded at standard size.
I would appreciate any advice from others more technically proficient than I am.