It would be interesting to see more information about this, looking forward to the follow-up article: "We will publish additional analysis related to respondents’ gender identities in the coming weeks."
Also I wouldn't be surprised if the numbers are actually higher: assuming the choices are exclusive, the way they are worded it's not clear how transgender is intended to be represented in the results. Not everyone who is transgender sees their "trans" status as a distinct gender identity (i.e. the emphasis in "trans-woman" or "trans-man" doesn't have to fall on the "trans" aspect). I think a clearer distinction would have been a separate question "my gender identity matches the gender I was assigned at birth" (instead of distinguishing between male, female and "trans") but that might have overcomplicated things.