They're now tired of fads since their own preferences have prevailed. Like all revolutionaries, Boomers became conservatives once they got in control. But, the trend is undeniable. People are hungry for the mystery side of religion. I suspect it is no fad at all, but signs of a mystery-deficient diet on worship.
Humans get hungry for what they've been missing in their diet.
Each generation seems to raise one aspect of God so high it blocks out His other characteristics. Our generation has made God into a fishing buddy. To us, God is primarily a friend who loves us no matter what. He's a buddy who accompanies us everywhere, always affirming and encouraging so that we can succeed. He's as close as the mention of His name.