Just for posterity's sake, here is my reasoning on why I voted for Minny. In order to beat a LeBron led team, you need to be have one of two things.
A) A squad that is overwhelmingly more skilled in many, if not all, other areas.
B) A SF who is capable of making LeBron work for his points, and also capable of getting his own (to varying degrees). Here's the short list of players I view as fitting the criteria. Kevin Durant, Carmelo Anthony, Paul George, Luol Deng, Paul Pierce, Kawhi Leonard. If you don't have one of those players, you likely aren't winning. Even then, it is still difficult if the rest of the team isn't also at least slightly better.
None of the teams Minny faced in the playoffs had one of those players, except for Portland, and I just didn't think Portland was good enough otherwise.