Misuse of authority doesn't invalidate that authority, I agree. But the lesson it teaches is obvious: that those in authority must be accountable, not only to God, but to the wider community. This implicitly means that the wider community has authority over those supposedly invested with authority. In truth, the authority given by Jesus rests in the entire community, that is, the People of God, not just in the bishops. To claim otherwise is unscriptural and a conceit.

You missed the point about those apologies: they were an official and high-ranking acknowledgement of evils committed by present-day representatives of offending past organisations. This is important. Unacknowledged evil is unrepented evil and therefore evil that is more likely to be recommitted.