This is the first time you've looked at that TBW number?
You're looking at a single snapshot in time.
The first few weeks or months, it gets a lot of writes. You're setting things up, installing, deleting.
That use curve flattens out after a little while.
2TB in 2 months may turn out to be 3TB in 6-8 months.
Monitor that use over time. Weekly at most.
Also, how the malware situation? What else do you have running on this system?