Mufti Abu Layth refutes Nouman Ali Khan's logic of hijab / head covering being mandatory for women

Nouman Ali claimed that people who interpret khimar as shawl & not as head covering are wrong, because the Arabic word does indicate head covering. But Mufti Abu Layth proved that even if khimar means some sort of head covering, verse 31 of Surah An Nur still does not order women to cover their heads.