I never heard of this quote, but "heard" something similar a while ago, must have been 2020.
I was watching a live worship session on Youtube and it was beautiful, kept my mind at peace.
Now mind you at the same time I was also a perfectionist, which means you tend to see imperfections in others.
Now at a certain point the singer's voice broke as she was hitting a high note. But before I could mentally register the imperfection I heard or felt such a clear gentle voice that said: "that was the most beautiful part".
In an instant it reframed the imperfect into perfect for that moment and thus forever.
And that's what your quote encompasses. Good read, thanks for sharing.
In the same vein, the most beautiful part of Patti Smith performing "A Hard Rain's A-Gonna Fall" at Nobel Prize Award Ceremony is when she mistakes the lyrics. Whenever I need to cry, I watch that video.
Cracks in the voice are so visceral. One I love is in the Rolling Stone's Gimme Shelter, Merry Clayton is just about screaming and her voice cracks and they kept the band's cheering reaction to it on the record [1]. Truly a case of the subject matter trying to break out of the medium.
Related is that a lot of cultures embrace intentional imperfections in art for spiritual reasons, as it conveys authenticity and humility in the face of perfection. E.g. Persian flaw [2].
[1] https://en.wikipedia.org/wiki/Gimme_Shelter
[2] https://en.wikipedia.org/wiki/Persian_carpet#cite_note-68