my impression from reading and participating in this thread leans towards an implicit bias towards DM as world builder and primary story creator and the expectation that setting exploration and dealing with procedural conflicts should be a primary priority for players in general, not just in a specific game run by a specific person. I mean we all have our expectations for players and its entirely fair to have them. To universalize our play priorities to a much larger subset of people is problematic.
I think that assumption (bias) is present in some posters, but not all.
But there are some posts - I've pointed to a few - which try to reply to those who obviously don't share that assumption from a premise of the truth of the assumption. Which is basically pointless: eg if someone is explaining how, as s/he approaches the game, the GM is first among equals for setting content creation, it is pointless to begin a reply to that person from the premise that the GM has unilateral power in setting creation!
The argument that if DMs restrict things then they are being high handed and dictatorial and only care about their fun is now 29 pages long.
<snip example>
That is the kind of player BS I am talking about when I say entitled. And I think he was unreasonable and selfish.
What you describe in your example doesn't seem to me to have much to do with player "entitlement" vs GM "authority" at all. The GM wasn't trying to restrict things by way of exercise of her authority as GM: at least as you tell the story, she was motivated by mechanical rather than world-building considerations, mostly her inexperience with the PF mechanics.
As my 4e game reaches its conclusion, my group is gradually warming up to start a new game with a new system. It will be our first time playing this system together, and I have expressly said that, because of our relative inexperience, I woud like to keep PC builds fairly vanilla.
To be honest, for me there is a degree of tension between (i) "K" being a friend of your GMing friend, and (ii) "K" wrecking your GMing friend's game. "K" doesn't seem like a particularly good friend, if he's trying to bully your friend into doing something she sincerely doesn't believe she is qualified to do.
But to my mind, at least, this is not very analogous to a GM saying "No tieflings because in my world civilised folk kill them on sight".