If you are trying to use sync, my recommendation would be to reduce the amount of data that odrive has to deal with. This means adding data to odrive's scope incrementally and unsyncing items that have already been backed-up. 72TB is, presumably, a lot of objects to track (millions?).
Remember that sync is concerned with both sides of the equation. It needs to track changes locally and remotely and try to reconcile those changes in a timely manner. The larger the dataset, the more work is required, and that work is constant. I expanded on this a bit above: https://forum.odrive.com/t/backup-one-way-sync/1058/11
As I stated in a previous post, if you really need to backup your data you may want to look at another solution until ours is available.