To me these arguments involving decoherence only show that the classical world is consistent with the quantum world, and indeed place constraints on the two the

To me these arguments involving decoherence only show that the classical world is consistent with the quantum world, and indeed place constraints on the two theories in order to achieve this consistency. But in no way does decoherence (exponential suppression of off-diagonal terms in a density matrix) imply collapse of the state vector. In other words, we don't know why anything happens! It's such a beautiful perplexing quandry, and I just don't understand this attitude of "nothing to see here, move along".