Oh, sorry if my response was too basic-level for your experience.

I get what you're saying about "cis men" being explicitly about gender. I took it as meaning phenotypic males, and that they used "cis men" either for simplicity (perhaps to avoid getting into the details of trans people that they thought was irrelevant to the point they were making) or because they were just imprecise with their language. It's also possible it was based off of something from earlier in the conversation that we can't see because it's just a screenshot.

Anyways, I agree, it was poorly worded, but I think the point they were trying to make was pretty straightforward (unless you insist on interpreting what they said to be something about genes affecting gender expression, then it doesn't make sense).