Suspect that, for the individuals who would have to put their reputations and jobs on the line by making a Boyle hire, there is not enough confidence/certainty in the upside - and too much concern about the areas of question/ doubt ... and the consequences (to them) if it did not go well & the reason was directly related to one of these areas of question.
One of the chief difficulties in considering Boyle for a major HC position is the lack of prior college HC experience - That lack does not mean that he can't do the job - but in reality, the basketball fan & media community will be totally unforgiving of any errors that could be attributed to that lack of experience - - and they would be swiftly calling for the heads of those individual(s) who chose to ignore conventional wisdom and employ someone with an experience deficiency.
Nonetheless, at some point, if Boyle's price point is attractive, somebody may get courageous.