I see this from a very different perspective. I think the presence of the niqab in public space in non-majority Muslim countries and, indeed, some majority Muslim countries breeds factional distrust between communities that has huge political implications.
The reality of the niqab is that it is a religio-political statement. You cannot get away from this, whether it is an enforced dress code or chosen. In fact, in places where it is chosen, and not mandated, the tension it creates is significant.
In Lebanon, for example, it is seen as a sign of Sunni radicalism, sponsored by Gulf states. The attitude to it in Beirut is one of suspicion and malevolence. In Turkey, it is seen as the mark of the invasion of theocratic conservatism from the hinterland and a direct challenge to the legacy of Ataturk.
My perspective is that young Muslim women who choose to wear the niqab in the West do not fully realise what they are doing. They think it is a question of religious repression and freedom to practice their religion; they do not realise how the niqab is seen by others as a mark of adherence to a particular theocratic political system and as an unwillingness to integrate.
And these two issues have a huge impact on how Western society views its unspoken contracts and how western societies work. For one, we are just not set up to deal with non-facial recognition.
I personally dislike the ban, but I think it is a crying shame it had to come into effect in the first place as it suggests there is a profound misunderstanding on the part of some migrants to western countries as to how they will best succeed in their new homes.