I think fans are well within their right to be frustrated about the last 2 weeks. As with any struggling business or team, the blame gets placed on the leader whether that's fair or not. Prohm seemingly chooses to do his coaching/teaching in practice and leaves it up to the players to win or lose the game unlike Bill Self, Bruce Weber, Chris Beard, etc. who are puppet masters pulling all the strings during the game. As fans, this leads us to have to do a lot more speculating and draw conclusions with limited information because we have no idea what Prohm teaches in practice and what the team looks like, all we can see is that the in-game coaching/adjustments are very limited. Since Hoiberg was great at drawing up offensive plays and seemed to have a good feel for substitutions and using timeouts, that adds more fuel to the fire whether that's fair to Prohm or not.
I think some people have hit the nail on the head when bringing up the assistant coaches, which almost never get talked about. John Beilein hired a defensive specialist as his assistant last year and all of a sudden Michigan's a completely different team. We certainly don't have the resources or cachet of a program like Michigan, but I think for us to take that next step, Prohm needs to take a hard look at his assistants this offseason and do some due diligence and find someone with ties to Tony Bennett, Bo Ryan(I know he's no longer coaching, but there should be plenty of assistants still coaching that worked with him), Chris Beard, Bruce Weber, etc. that can bring that defensive knowledge to our team. After almost 4 years, I think it's fair to assume that even if Prohm is spending 75% of practice on defense, his message and/or methods aren't translating to games. If he can acknowledge his limitations and find someone who can teach defense at this level, I think we have the right guy, but if Prohm doesn't want to do that and just sticks with his current group that are mostly from his same coaching tree, then I think it's fair to have some long term concerns about our ceiling with this staff.