Unless I'm missing a comment from the poster, I don't think there's an argument being made to force this actor to grow body hair just for this role.

Just that it's odd that they'd go through the effort in makeup to make them appear dirty and unkempt, but don't bother to include body hair. It's a common practice in makeup to add beards to men to give them a more unkempt appearance, but not armpit or leg hair on women even though most adult women grow hair in these areas.