TERFs aren’t wrong to say that sex is material and that womanhood is a political class. Where the TERF analysis goes wrong is in where it locates the boundaries of that class. There is no singular, universal experience of what it means to be a woman – for any biological criterion TERFs put forth, there will be some cis women who don’t meet it. For every social experience of marginalization that has a gendered component to it, there are some cis women who do not experience it. The common thread in defining woman-as-a-class is not any essential quality – it’s the inherently social and political act of identifying with that class, and therefore being seen (at least intermittently) as part of that class.