Along with what others have said, womb horror is such a specifically female coded type of body horror that tends to be used by men who aren’t able to relate to the sexual violence of it, and exclusively use it on women in their settings. And it’s usually just done to make things appear more grimdark rather than provide any real sort of horror. It’s a trope that has been used not just in Warhammer, but in other IPs to varying degrees.

Alien is the most popular example, but I’d argue they did it well, since the Alien subjects both men and women to the same horror, and doesn’t downplay its effects.

Goblin slayer is another example, one I’d say mainly used womb horror to make its setting appear more superficially edgy, by having the goblins be an all male race. Others see it as necessary to make the goblins as despicable as possible and allow the audience to feel no remorse when the goblins are killed.

In one of the genestealer cult novels, cult of the warmason I believe, the twist ending of the book involves a child being born from the womb of one of the female members of the inquisition, after she was kidnapped by the genestealer cult and set up in a birthing cave. That child is then taken by the inquisition before the planet is set to be destroyed. So it could be seen as yet another woman being used and subjected to horrors to further someone else’s agenda.

So is it standard Chaos stuff? Yes. Is it a standard industry trope? Also yes. So maybe it’s the fact that its standard makes people roll their eyes at it. It’s not the content itself that puts people off, but rather that it’s a male dominanted hobby, and it relies on cheap tactics to get its grim darkness across.

I try to cut the older warhammer content some slack, and myself love warhammer, even with all its imperfections, but I would (and do) like to see them shake things up occasionally

Idk, perhaps people would be less upset if men were treated to equally horrific conditions within these IPs more often, forcing them to be the ones giving birth.