What part? The "Mothers for their children" part? That stretches the definition of "vocals only"
Yea but how many bands have many sections with only vocals? I think that's a bit of an unfair challenge. It'd be better to examine sections where the vocals are the main focus. Like the beginning of Surrounded or Far From Heaven.
I agree with the above strongly.
A lot of times, it's really obvious that the music was written before the vocals. Something like About to Crash has so much stuff going on under the vocals. It feels like they recorded the music and were like "oh yeah, singing has to happen here. We have to fit it somehow." The music under the vocals is just so melodically and rhythmically dense. It feels like a disservice to JLB a bit.
On the other hand, you look at a song like IT where, even though JLB isn't in the song a lot, he's clearly the main focus of every section he's in. There's no overly dense rhythms or competing lead melodies to distract you. It's about quality, not quantity, and the quality is there.