Treating a face covering as "just a piece of clothing" is insulting, both to those who wear it, and those who object to it, which includes most Muslims.

It is not. It has a specific purpose, which is to make normal social communication outside the family impossible for women. That also makes it impossible for those around that woman, which is how it affects others, and makes it a social issue, as the ECHR has recognized in approving the ban in Europe.