I do remember a priest in the past explaining to us what he was doing to make the Mass shorter. How do you know one priest didnt say that to his parishioners in the OP parish?
That’s the point we don’t know. So in Catholic charity, we assume it was made shorter
for the best of intentions. Two examples I already gave, the priest has another Mass to celebrate and he needs to leave at a time that allows him to get to it, or the priest has health issues. Another would be
his parishioners asked for it to be shorter.
So while we don’t know the reason, we are to assume they were good reasons, especially since licit options were used.
At the abbey where I go to Mass, everything is in Gregorian chant and French plainchant. Sunday Mass is about an hour and a quarter, weekdays on ordinary ferias or memorials (i.e. no Gloria or Creed), about 35 minutes. The community is aging rapidly, with the average age now 70, and many monks in their 80s and a few in their 90s. In summer heat, they take measures to shorten the Mass: apostle’s creed (sung in Latin!) instead of Nicene, brief homily, if it’s a long offertory antiphon in the Gradual they omit it and there’s a brief organ piece instead, EP II (and they do use all 4 main EPs throughout the year) things of that nature. Everything is done according to rubrics, but it takes about 15 minutes less. It’s all done for a good reason, and within appropriate boundaries. Moreover as a conventual Mass, it is for the monks, not the laity though the laity are welcome to attend.
My point in all this rambling, is that there are many
licit reasons to select a shorter
licit option to shorten the Mass.
Plus, priests are human. We only typically see him at Sunday Mass, but he might have a full workload during the week. He has to administer the parish (no easy task) with tight funds, he has to make sick calls at all hours, he has to prepare a
riveting homily for every Sunday, he has to preside at weekday Mass, he has to travel around to various retirement homes to celebrate Mass for shut-ins, he often has to celebrate Mass on Saturday evening and/or another Mass on Sunday at another parish half-way across the county (that’s the reality where I live), and at the same time keep liturgy geeks like us happy… or give us something to gripe about. So we end up judging his whole week’s performance on the one hour on Sunday that we see him.
It hardly seems fair. Nor charitable.