Catholic schools teach English so the people can read the translation in the Latin-English Missals. Latin was also once widely taught, in Protestant schools as well as Catholic ones, so more people could once understand it than you think. Latin was once, and should be again, a common cultural heritage in the West whose use was not limited to the liturgy.
Yes, I’m sure they discussed that a bit at Vatican II . . . at some point though the old common languages just die and are replaced with new ones. Greek, Latin, French, English . . . what’s next? Pray it’s not Chinese!