I agree. And nobody seems to have foreseen the problems with a vernacular Mass. First (for English anyway), to my ear contemporary English is not an especially good language for public prayer, which I think must have an element of the poetic -- and contemporary English poetry has moved in an intensely private and idiosyncratically personal direction. Contemporary English is well suited for prose in the hands of a master (though even here there's an "individualism" that works against it as public prayer) -- and I believe English is becoming or has become the language of science and of business, neither of which is suited for public prayer but both of which are the forms most of us lapse into. Unfortunately, too, a requirement for translators of the Mass seems to be a tin ear.
Then -- whose vernacular? I saw an article recently about a parish with a large immigrant population, mostly Spanish or Portuguese speaking, a source of controversy, with the Spanish-speaking having the numbers at present to prevail. If Mass were still in Latin, nobody would have an advantage. And we really don't need more sources of controversy.
And then there are the advantages of a "dead" language: it doesn't change. Words don't acquire new connotations. (I still find it hard to accept "Heaven and earth are full of Your glory" because "full of" has so many -- shall we say -- less exalted connotations. Words also don't have local connotations. I worked years ago with a guy who had studied Spanish for a long and time and traveled in South America trying to perfect it. He said that sometimes it was only a matter of a few miles between a word that was perfectly innocent and humdrum and the same word as an obscenity.
I love Gregorian chant, too. The parish I was in when these changes started coming used some of the English set to chant. Some of the arrangements were very pretty, but I think unsustainable over a long passage. Chant grew up around Latin, which because of the structure of its declensions and conjugations has very few monosyllables apart from prepositions; English has many, many nouns, verbs, adjectives that are monosyllables.
I might as well put in here, too, that I hate those stupid little "missalettes." I see no point in them: the responses are few enough to memorize in no time, and -- English being my first language -- I have no need to follow along in reading what I'm listening to. They are an anachronism that has lost its point -- we used Missals with the Latin Mass because we had to, and as I recall it the effect was an aid to concentration. (We also had a place to keep holy cards and prayer cards for the dead.)
Maybe we all just love best what we grew up with.