What has happened is that this Sesame Street approach merely transfers one form of communication style from the secular pop arena to the sacramental life of worship where it doesn't belong. It is part of a larger drama of therapeutic touchy-feelyism in clerical culture, an exotic topic in itself which would require multiple levels of psychological and sociological explanation. What really needs to happen is that no one should be allowed in "music ministry" work who has not received formal (and orthodox) Catholic training in the history of Catholic sacred music. The mischief of the music ministry mafia can be curtailed when enough people stand up and protest the silliness of this. Will we have Eminem-inspired "Rap" Masses next? The basic problem is the relativistic idea that the Church needs to follow the forms of contemporary culture in order to be relevant to this or that culturally challenged victim group in our midst. The other problem, of course, is the self-appointed nature of the minority faction (the music ministry mafia) who impose these forms on the rest of us. As with other and more unsavory problems, many bishops turn a blind eye to such matters. It is also a racket. Someone is SELLING the music books for this goofy style. As with so many other banalities and asburdities of the post-Vatican II landscape which have contributed to the current wasteland, the conservative critics can be dismissed as narrow, mean-spirited, and not up to date enough, etc. ...And the beat goes on...
You almost feel sorry for future church historians who will have to wade through this mess trying to make sense out of what exactly happened to the church in the U.S. during this period. In many cases, "the lunatics were running the asylum..."
They're called "Rave Masses" and they've been around for a long time -- well before anyone knew who M&M was.
(They're usually not advertised in your parish bulletin, though.)
The creepy thing is that the style of V-2 Catholic liturgical music has not been "pop" for over thirty years! It's another V-2 fly in amber, stuck in the '60s.
Much like the way Catholic philosophy and theology (and all Church pronouncements) are couched in the language of '60s existentialism and phenomenology.
(Let's go down to the coffee house and dig the happening.)
There is an Austin-Powers-like quality to much in the Church, where time is frozen to the era around 1963-69.