There are many things to like about the kid, and he clearly is not a horrible QB who will cost you games.
But it's also clear that he is not a QB who will win games for you. All aspects of the team have to line up ideally for him to come away with a W. In a league of parity though, usually the QB separates the winners from losers and there are always a handful of games where the QB needs to put the team on his back and will them to victory.
Somebody shared a tweet after last week's game that said it was the first time as a Bills that he won a game they trailed in. That wasn't technically correct, as the first was the Titans game last year. That game also counts as the only fourth quarter comeback that TT engineered, although it doesn't qualify for Pro Football Reference comebacks because Bills scored early in the quarter.
So, I looked at TT's series with Bills down by one score or less with 2-4 minutes to go in the game (so hardly desperation time). Here are the sad results:
NE1 - 0 FD - 0 Yds - 1 INT
NE2 - 2 FD - 32 Yds
KC - 1 FD - 19 Yds
Phi - 0 FD - -2 Yds - 1 INT
Balt - 0 FD - -8 Yds
Miami - 0 FD - 0 Yds
Six opportunities, zero clutch drives.