You are looking at things from the wrong perspective (others as well). First, it has little to do on whether the decision to play Tyler was the main reason for losing the game at the end, although one can easily argue that when Tyler entered the game in the first half, the game was certainly still winnable. No doubt about that, most feel like AG certainly would have matched better against Pickett with his length, would have given us a better chance to put some points on the board, and contrary to the parallelism of taking a knee that someone else made, we should always play to win, not play not to lose. Especially in the BR game. And while the decision not to play AG is questionable, the decision to just insert him at the game in garbage time is certainly unjustifiable.
More importantly though, there is no denying that there was a mass exodus last year when 6 players with remaining eligibility decided to leave the program, including all of BU's own recruits with remaining eligibility. There is no denying that there were some "issues," some parents had negative feelings, others took the high road. The last thing you need on that front is having now a parent being livid and openly and publicly criticizing the coach. It is extremely negative for the program and recruiting, especially when the brother of that player is a highly ranked national recruit. Add the fact that some powerful coaches have also publicly made negative comments about BU, it shows there are some serious issues with relationship building both internally and externally, and there is no denying that no matter how many defensive articles Werner and Piper write. That is the real issue, especially for a program that is currently hurting on the court but also on the recruiting trail.