My friend’s MIL doesn’t acknowledge her grandkids on holidays because it doesn’t occur to her. It’s not a priority for her. She was/is a recovering alcoholic (forced into it due to ending up in the hospital due to her drinking). She’s not in tune with anything other than what is happening “right now”.
In your case, though, because you said she is estranged from you and your husband, she is also estranged from your child, because your child is an extension of you two. If she doesn’t want to deal with you, it’s easier not to deal with your child, because your kid is a constant reminder of you, or she’s worried that she would have to discuss issues relating to you or your husband, even if that is not likely to happen. Doesn’t matter though, because it might happen, and she doesn’t want to chance it.
Also, I’m guessing that the woman doesn’t care for your child’s gender situation, because she has some type of objection to publicly acknowledging it, because that might equate, in her mind, to condoning something “bad” that she might not see as a fact, but rather a “bad choice” that your child, or you as the parents, have made, rather than just understanding “what is”.
One of my relatives and I got into it regarding gender, and he was angrily adamant that people are either male or female at birth, period, and that sex and gender are exactly the same thing. Any further discussion with this person lead to ugly, angry exchanges.