The problem is that you are trying to scan the whole of the linked Google Drive initially. In a large number of cases users are not interested in syncing their whole GDrive but rather only specific folders.
I have made the suggestion before that as a default when you initially connect a new GDrive account, it should not automatically select the whole drive but rather give you an option to only select the folders you are interested in syncing (like you can do with selective syncing). The initial sync can then be limited to only the selected folders which in most cases will be a fraction of the total drive. This will significantly speed up the initial sync and also any later re-syncs.
I was promised that this is a feature that was being looked into but as always its been months (just look at when this thread started) and its still only pie in the sky. 
I still do not understand why you feel the need to continuously keep doing full background syncs even if one has set up a selective sync folder(s) set. This is a total waste of time and resources by storing folder data that sit totally outside of the selected synced folder(s). All of this adds up to these huge delays when doing initial syncs and re-sync!
Here is yet another thread dealing with the same issue and same empty promises: