No, it is how you think the rules should be played. If the rules were as clear cut as you think, we would not be having such discussions. These obligations are not absolute. They are things that the DM can opt to insert into the game, but that does not make it a rule to insert them into the game.
You may want to withdraw your strawman; nowhere are we discussing altering mechanics. The class itself is not being altered. Merely the prominence of class flavor.
Not really. IME, it just sidebars the discussion until it does come up into play. There may be multiple reasons for that, most notably both the player and DM leaving their relative expectations unstated. The player is not somehow contractually obligated to be the DM's whipping post because these things were not discussed prior. Hence, this thread about what reasons a player may leave a DM's table.