My opinion only…the Missal of 1970 was intended to be an “experimental” Missal. Priests would have a few years to see what worked and what didn’t by actually implementing these options at the parish level. Then, bishops would get feed back, consult one another and finally present their findings to the Holy See and a final Missal would’ve been issued sans most, if not all, options.
The problem is, 1970 was around the time the “smoke of Satan” entered the Church. It was
Lord of the Flies time for a bunch of ankle-biting priests, nuns and lay people who were finally able to take out their rage on the Church without fear of reprisal. Add to this the continuous river of liturgical changes that assaulted the people in the pews: vernacular, turning the altar around, tearing out High Altars and Communion rails, laymen reading scripture and distributing Communion, Communion under both kinds, Communion in the hand, ad infinitum, ad nauseum…perhaps the Holy See decided that, in the midst of Church-wide anarchy and seemingly weekly changes, it was best not to try to implement yet another entirely new Missal so the 1970 version stuck.
Or, perhaps, there’s been some other cover story put out about why we have so many options. But my version makes the most sense to me.

I mean, seriously. Does the Mass of Paul VI strike you as a finished product? It doesn’t me. Seems like it should be stamped “DRAFT.”
So, since reviewing the new Mass after just a few years of use was impractical, I think now is the perfect time to do it. We’ve had more than a generation to find out what works and what doesn’t. Time to get out those scissors and start chopping. Why, for instance, is there any point whatsoever in having a Eucharistic Prayer (#4) that nobody uses? Why have two options of the Penitential Rite that duplicate the Kyrie? Why allow the [text in brackets may be omitted] when it might take a whole minute and a half to read it? What’s the rationale behind dropping the Amen from the Pater Noster? Why not just let the congregation sing or recite a Psalm instead of making it a *Responsorial *Psalm?
The '65 Missal may have been the logical progression and even, dare I say, an organic development of the '62 Missal but you can’t really impose that on the Church now. Oh, people would squawk. But I think, with all the brilliant minds we have in the Church, especially in the Chair of Peter, we could definitely streamline the current Mass and take it back closer to what the Fathers of Vatican II intended. Even just eliminating the options entirely and leaving everything else exactly the way it is would be splendid.
Or so it seems to me. :tiphat: