Because it's a mix of postmodern and modern (Marxist) frameworks. They inherently don't go together. The word makes literally no sense if you know anything about frameworks.

Sounds to me like people are trying to poison the well on criticism of identity politics by painting critics as nazis.

Ha! That's ironic, considering the right wing and their ilk are the biggest proponents of identity politics. It's just thinly veiled, as the identities they are defending are status quo, so they can just claim "we are being neutral, its the left that is divisive". And dumbass neoliberals eat that propaganda up because they have smooth fucking brains and can't see even the most blatant dog whistles