It's funny how tradition bound D&D is.Sure, one must not give credence or power to stereotypes - and that must be crystal clear from Session 0 onwards. However, it is not acceptable for a player to dump stat the two favourites - Int or Cha and then roleplay them as smart or charming (respectively), hiding behind the excuse that they should be able to roleplay their character how they want.
The fact is they dump stated to get a better Dex, Con or whatever and will as a direct result enjoy rolling with the consequent extra bonus continually through the game/campaign. If they had dump stated Dex - then I would not have allowed them to roleplay being graceful either, or a 7 Str character as strong - so I don't for Int or Cha.
They do not have to play 'dumb as a post' or 'trips over their tongue when they talk' characters, but I will be damned if they don't roleplay appropriate limitations at all. That is very poor roleplay, and poor gamesmanship, and I don't let it slide at my table as GM.
In ensuring nobody roleplays anything insulting or inappropriate, don't forget that the word 'roleplay' comes before the word 'game' and nobody forces anyone, ever, to dump stat...
The idea that there's a gap between the rules as they actually work and influence the game, and the traditional interpretation of what ability scores mean., and that this gap gives scope for alternative interpretations...just does not compute! It's either done the one way or it's "bad" role-playing.
I'm curious about whether people also complain about the art or mini's players choose to represent their Strength 20 Fighter. "It doesn't have enough muscles for the strongest woman in the world. Go back and find something bigger and bulkier."
I'd imagine for consistency's sake the same people wouldn't allow anything to be reskinned either. Whatever fluff text is in the official write-up is what you have to play. Anything else is "bad" role-playing.