Yes, it was pretty high initially. For one, Tesla had contactors failing in the battery pack, and in the initial pack version, it was not easy to service these without changing the whole pack.
I guess the question is whether Model 3 and newer Model S have high pack failure rates. Does he still work for Tesla?
FWIW, the battery pack in my PHEV was replaced under warranty as water had contaminated the pack. (Seal was not fitted correctly in the factory - known recall for VW electric vehicles.)