Jim, the fact that your personal experience with playing in your parish did not involve hippies music or 60s or 70s music does not mean that others of us have not had the experience in our parishes.
(Also the Weston Priory monks wrote a lot in the 1970s. I should know as the folk group I spoke of was in a church in Vermont and so well, these were LOCALS we did music thereof).
Many of us are more than capable, having the musical knowledge, of discerning whether a guitarist in Church is playing something like Silent Night (yes, the melody was composed for a guitar originally), something from Haugen in the 1980s, something from Bob Hurd in the 1990s, something from Stephen Warner in 2000, (all Church musicians), or folk songs like The Spirit is a Moving, or pieces from the 1970s such as “All I Ask of You”, And I will Raise You up", “A Child is born” (Weston Priory), etc. We don’t see guitars and automatically think, “Oh no, hippie music!”
An organ likewise not automatically instill, "oh NO, hundred-year-old dirge music’ either. I know you won’t believe me but I have heard the organ playing (admittedly for wedding ceremonies) such pieces as “Jesse” (I won’t bring fresh flowers for you), ‘Barry Manilow’s
“Could it be Magic”, and Christopher Cross’ “Sailing”. So I don’t look at an organ either and think, “Ah, traditional old Church standards” either!
Now mind, Jim, this is not a personal piece trying to call you out or anything, far from it. I’m sure that your personal experience has been exactly as you say.
But please do realize that just because other people have different experiences from yours, it doesn’t mean that they have been mistaken, or that things like 60s and 70s and hippie music are not still being played at parishes in the U.S. They have been and they are. (I offer it up, myself, so in that sense, I’m pretty much going along with what the article says. That doesn’t mean that I can’t wish it were different.)