Help me understand John Coltrane .... seriously.

I studied tenor sax from Grades 4 through 12 and my music teacher was a retired jazz musician.  Coltrane is what is known as a "progressive" jazz players.  Progressives use a lot of atonality, which can sound like they're playing the wrong notes, and they also don't strictly observe things like rhythm and meter.  Coltrane got more progressive as the years went on. I used to imitate him by. just hitting sax keys at random, which my bandmates thought was pretty funny. I much prefer "traditional" jazz players who are more melodic like Stan Getz on tenor, Paul Desmond on alto and Gerry Mulligan on baritone.  But if you're still interested in exploring Coltrane, he did an album with Duke Ellington - quartet of piano, sax, bass and drums -- which is about as accessible as Coltrane gets.  

"...I feel, strongly, that what we think of as just who WE are is learned."

John Erik Locke! Tabula rasa auditoria.

When it comes to the instruments of wind, I found out that masters at Guča Festival play no second fiddle to those we mention here.

Unless you truly dread it for non-musical reasons, which you will not after about an hour of following the festival routine, you will never have to convince yourself why you like it. It is exactly the opposite from the mystery of the dim room loneliness with a glass of an expensive drink in hand.

"Progressives use a lot of atonality, which can sound like they're playing the wrong notes, and they also don't strictly observe things like rhythm and meter."

Hmmmm, that explains it.

I think they are aware of the rhythm and meter but they are allowing themselves to not adhere to traditional rules regarding rhythm and meter.
I can't tell you how many times I've been listening to a jazz group that I was sure was totally lost regarding the form, only to have them suddenly come back together and prove me wrong.