I largely agree with you, but it's too easily to overlook melodically/harmonically complex songs by people like Brian Wilson, Stevie Wonder, Bacharach etc. As much as we love jazz around here, and as much as we admire jazz musicians, they can fall into familiar, comfortable patterns as easily as anyone. A lot of post Beatles pop songs don't have the type of harmonic structure that many jazz musicians like to blow over. I will admit that this is a gross generalization, but I think there is some truth to this.
When I used the word "superficial," I simply meant that the first argument could be used as a smokescreen to mask some other reasons for the break between pop and jazz; I didn't mean to imply that it was superficial to believe that.