Thoughts...The wind blows wherever it pleases. You hear its sound, but you cannot tell where it comes from or where it is going. So it is with everyone born of the Spirit.
1. It almost seems as if it would make easiest sense if we deleted "everyone born of" from the last sentence (leaving "so it is with the Spirit"). This would mean that the Spirit goes wherever He pleases and cannot be managed by humanity. Perhaps Jesus was, in a subtle way, rebuking Nicodemus and his fellow authorities for thinking they could control who was "In" and who was "Out" of God's kingdom via institutional Judaism.
2. BUT the "everyone born of" is indeed part of the sentence, which seems to indicate that the comparison is not strictly WIND compares to SPIRIT, but more accurately WIND compares to EVERYONE BORN OF THE SPIRIT. The most natural way I read this suggests that non-born again people just can't figure out born-again people. They march to the beat of a different drummer, so to speak. This point has merit, but feels sorta odd to me in context.
3. Then I started thinking more about the conversational context. Nicodemus is struggling to understand this "born-again" thing b/c it's not literal/physical. So maybe the point of the analogy is that just because something can’t be directly observed or managed by human institutions, doesn’t dictate that it is not a reality. Close to point 1, I know.
That's the best I can do with summarizing my scattered thoughts on this. I was hoping for some thoughts from ya'll