I sort of agree with you, but I don't think the problem of clueless cis people misunderstanding gender politics should be blamed on Black anti-racism activists. Cis people of all races can be flaily and anti-helpful, but it's nothing to do with being "woke" in scare quotes.

It sounds like the parents in the letter have in fact gendered their daughter (presumably based on biological sex given they talk about her being "mistaken" for a boy when under 2). They use female pronouns and refer to her as a daughter; their idea of gender neutral is not about waiting until she's old enough to express a gender identity. It's about treating her as a person, not an ornament. Which I hope would not cause any harm or blame to a trans kid either, but I agree that the overreaction to liking sparkly princess stuff is a problem.