Google Drive for cloud backing up mac - and losing a lot of local storage space?

Just subscribed to the 2TB package of Google Drive to try to backup my Mac "continuously". However, within hours the 80GB+ of space I have on my Mac has now decreased to 20GB, and I am getting the out of memory errors.

I do not have sync checkboxed, but it seems that there is a lot of unnecessary previous local solid state space being lost here? What can be done?