For one, I have never even heard of an official Church sanctioned boycott of an apostate. I suspect that it could happen, but that alone seems highly unusual. If it happened, I suspect it would be more along the lines of Bishop so and so spreading the word quietly that we should not patronize so and so's business.
I don’t think a bishop and a high counselor mouthing off in Sunday School out of frustration counts as an “official Church sanctioned boycott of an apostate.” You concede that it is part of the Utah culture to avoid supporting the businesses of apostates. Why is it so inconceivable that someone entrenched in this culture might achieve a position of local authority, and might, in a moment of frustration, actually say out loud what might just be normally whispered?
Second, the purported boycott in this story was not only sanctioned by the Bishop, it was announced in Church, which takes the story to a whole new level. This is where we are getting borderline on plausibility.
This doesn’t sound like a second point but a reiteration of the first point, so see above.
Third, the boycott seems a very harsh response to a member asking hard questions in a joint priesthood/relief society meeting. What is the likelihood, in all seriousness, that simply asking hard questions in a meeting will result in such a harsh penalty. Would any Bishop you have known do such a thing?
I agree with this, but it is possible that there is missing background information. This would be more plausible if the questioning member had already been a bit of a thorn in the bishop’s side and was getting a reputation as someone who was asking troublesome questions and causing distress among fellow members.
Fourth, not only is there a boycott, but it will be enforced by denying temple recommends to otherwise faithful members that violate it. Okay, this is going over the line of plausibility. It is just too crazy
I think it’s quite plausible that some members could interpret the temple interview question about associating with apostates in such a manner. Of course, it’s been a while since I’ve been in a temple recommend interview so I don’t really remember the exact phrasing, but do you deny that it could be interpreted by some in such a manner? Particularly in some rural Utah areas?
Fifth, not only was the Bishop subject to a monumental lack of judgement, but a high councilor stands up and backstops the Bishops boycott and enforcement measures! And no one in the group says anything.
I find it completely believable that no one in the group would challenge the bishop. Part of the LDS culture is to respect one’s leaders by virtue of position. If someone had a problem, I think the preferred route would be a private talk about the matter. I don’t find it any more implausible that a high counselor would agree with the Bishop than that the Bishop had the idea to begin with.
I think this boils down you not finding it plausible that leaders would say out loud what is normally whispered. I think it’s plausible, and given enough time and wards, inevitable. But I do agree that the story as offered does not provide enough details to meaningful judge its plausibility.