I'm not convinced that being true redeems any and every statement. For example you can lay out a case for eugenics unacceptable in almost any moderated forum while only making true statements.

As for the linguistic element in your question, "X is Y" in conversation typically means "X at large", allowing for some anomalies but otherwise making a statement about the whole group.

Selective ignorance is a dangerous strategy... Far better to evaluate the facts as fully as possible and find the actual reasons for and against. However a straightforward argument for eugenics is probably not very accurate or broad in its consideration. In that sense I guess it could be inaccurate or true but incomplete and/or misleading on its own.

> I'm not convinced that being true redeems any and every statement.

What does that mean?

I'm curious about what obviously true biological characteristics of women reinforce negative stereotypes about them, if you have any. Otherwise I don't really see the point in the hypothetical.

I can't come up with any right now.

Fortunately, I can come up with one about men: Men are more physically aggressive than women. I believe this is true, a negative stereotype, and has biological basis.

Pop in an 'on average' and I would agree with you there. Bearing in mind that the intra-group variance is probably comparable to the difference in the means of the groups.