Is it improper to address someone as Sir or Ma'am based on their looks?
この場合、次のような聞き方ができます。
ーIs it rude to call someone Sir or Ma'am nowadays?
「今時、SirやMa'amと呼ぶと失礼になりませんか?」
rude「失礼な・無礼な」
ーIs it improper to address someone as Sir or Ma'am based on their looks?
「見た目でSirやMa'amと呼ぶのは不適切ですか?」
improper「不適切な・間違った」
to address someone as ...「人を…と呼ぶ」
ご参考まで!