Unfortunately, I think it is undeniable that the expanded license to use the Extraordinary Form has empowered critics of liturgical form to take the position that the entire reform movement has been a mistake & that we should just do a wholesale return to the Tridentine form. This is no doubt a minority, but it is a very vocal minority. I wonder whether Benedict XVI would do the same again, with the benefit of hindsight.

Their major problem, as MSW rightly points out, is they seek a return to an ahistorical expression of the Liturgy, ignoring the currents at the time, including those by Pius X & Pius XII, which reformed elements of the Liturgy. They fail to grapple with their own "sources" in this respect, which undercut much of their arguments against reform.