I wish to propose a theory about Blessed Paul VI for which, currently, I can adduce some evidence; I wonder if there is more.
HE WAS UN POCO AMLETICO
(1) He relied upon dishonest people for advice. (a) From the Memoires of Louis Bouyer: "At different stages, be it with regard to the dumping overboard (sabordage) of the Liturgy of the Departed, or again in that unbelievable enterprise of expurgating the psalms in view of their use in the Office, Bugnini came up against an opposition, not just massive, but one could say pretty well unanimous. In some such cases, he did not hesitate to tell us 'But the Pope wants it!'. After that, to be sure, there was no longer a question of discussing it." Bouyer recounts how he once met Bugnini in circumstances in which the latter, mistakenly, believed that he, Bouyer, had just been with Pope Paul ... whom Bugnini was on his way to see. "On seeing me, he not only turned completely white but, visibly, was knocked for six (non seulement il blemit, mais, visiblement, il fut atterre)". "The answer was to be presented to me, but some weeks later, by Paul VI himself. Nattering with me about our famous labours, which he had confirmed, he finally said to me 'But why, then, did you put into this reform ...' (Here, I have to admit that I don't recall any longer which of the details which I have mentioned particularly irritated him.) Naturally, I replied 'But purely and simply because Bugnini guaranteed to us that you were absolutely set on it (avait certifie que vous le vouliez absolument).' His reaction was immediate: 'Is it possible? He said to me personally that you were unanimous in this respect!'".
(b) Bishop Tissier's biography recounts that when Archbishop Lefebvre was received in audience by the Pope, Paul VI was hostile from the start. It transpired that he had been informed, probably by Cardinal Villot, that the Archbishop made the priests whom he formed "sign an oath against the Pope". Given such shameless mendacity, it is hardly surprising that the Holy Father's mind was poisoned against Lefebvre.
(2) Blessed Paul VI preferred to compromise with disorder rather than to face it down. It seems clear, from Dom Cassian Folsom's Adoremus series of articles, that the provision of alternative Eucharistic Prayers was a pathetic but well-meant attempt to rein in the chaos which existed particularly in the Low Countries, where home-made Eucharistic Prayers were proliferating in (literally) hundreds. He was assured that the Hierarchy, given this concession, were prepared to restore order. (Big of them ... Traditionalists would also do well to remember that it was the provision of these alternatives which saved the Canon itself from being mangled ... better, surely, to be unused for a few decades than permanently debased?)
As well as the human and historical tragedy, there is an ecclesiological point here. If you blend together in one saucepan an exaggerated notion of papal authority (as analysed by Joseph Ratzinger) with the activities (described in detail by Louis Bouyer) of unscrupulous and dishonest and ruthlessly determined manipulative individuals who have the pope's ear, you are gravely at risk of having a disaster the results of which it may well take generations to mitigate. Quod factum est.