“Choose” is a very loaded word here. Yes, technically, they have a choice between wearing a hijab and an alternative, but what is that alternative? For someone in a conservative Muslim community, there is an extreme stigma against choosing not to wear a hijab, so it’s a choice between wearing one or being shunned. If it’s a theocratic country, it’s a choice between wearing one and death. Yes, technically a choice, but no more of a choice than being robbed at gunpoint and “choosing” to empty your pockets to not be shot in the head.