I'd argue the opposite. Strategically, if this doesn't work, the Borg now know you're attempting genocide against them. All that protects the Alpha Quadrant is the Borg's semi-disinterest.
If I'm not mistaken, only one person objected to the plan on its face: Crusher. Picard and Laforge objected only because they observed evidence of emerging individual consciousness in Hugh, and felt that using him in a particular capacity was amoral. And Admiral Nechayev expressed, in the name of Starfleet, her disapproval of Picard's choice, regardless of Hugh's transformation. That was Starfleet's values: one voice of complete dissent. Moreover, they disregarded it as an immoral action because it would bring an end to the war in which Federation citizens suffered and in which the Borg, for whom there was no difference between soldier and citizen, were the only aggressor. Whether or not it would have been effective is not a moral question.