I can point to a few dozens of parishes in Milwaukee which maintained two or three choirs (the adult choir being one, then one or two grade-school choirs) which sang for the Sunday and daily 'missa cantata' prior to 1965.
Milwaukee was unusually blessed, as the godfather of church music up here (John Singenberger) was educated at Regensburg, the home of the last major Church music reform (1880's.)
He stopped briefly in Cincinnatti, then came here and taught at the Seminary, but also was responsible for promoting good parish-level church music programs all around the Diocese. He was also regarded as a 'pretty-good' composer of church music; a good deal of his ouevre is still used in Milwaukee.
Milwaukee had a very active group of parish musicians which met regularly and during every other summer would also have a 3-day seminar; guest lecturer/workshop leaders included Roger Wagner and Paul Salamunovich, not to mention our own Sr. Theophane (Hytrek), OSF.
After 1965, but particularly after the arrival of Rembert, the deterioration in standards and mission was clear. Now we see parish "directors of music" whose BS in Knitting Arts and continuing education in "music" consists of learning about maracas and Bo Diddley hits.
I have a wealth of music by Singenberger and others of his ilk. A few churches were throwing away....."that old crap"......and I "caught it" before it went to the dumpster!