The way I look at it, alignment is simply an expression of the Absolute (rather than Subjective) Morality that exists in D&D by default.
Demons and devils are evil. They aren't misunderstood by do-gooders, they're Evil. Angels and other celestials are good, not just because they oppose Evil, but because they are Good. In D&D Good and Evil exist outside the perceptions of the characters (and the players). The alignment matrix in an illustration of where your PC’s actions and tendencies usually fall in that Absolute Morality, and shouldn't be used as a role-playing crutch or role-playing restriction.
BTW, I'm very happy there is no longer an XP penalty for changing alignments.
Demons and devils are evil. They aren't misunderstood by do-gooders, they're Evil. Angels and other celestials are good, not just because they oppose Evil, but because they are Good. In D&D Good and Evil exist outside the perceptions of the characters (and the players). The alignment matrix in an illustration of where your PC’s actions and tendencies usually fall in that Absolute Morality, and shouldn't be used as a role-playing crutch or role-playing restriction.
BTW, I'm very happy there is no longer an XP penalty for changing alignments.