Have the Buccaneers been slightly underwhelming? Based on expectations, yes.
But all things considered, Brady hasn't been "thoroughly unimpressive". He has been really solid all things considered:
- The combination of Learning a New System with a new head coach + No Preseason + Limited Offseason
- Bruce Arians having a reputation for having first-time Quarterbacks struggle and throw many interceptions (which Brady has only thrown 11)
- Very limited playcalling early on
- No continuity (Joe Montana, for example, brought his OC from San Francisco to Kansas City)
Still top 5-6 in all major QB stats, at age 43.