Opinions sought: Is this transphobic?

Someone wishing to disparage Chelsea Manning wrote, "As a woman* she* is still a treasonous weasel."

People can call Chelsea Manning a treasonous weasel without being transphobic. (I myself don't like what I know about Caitlyn Jenner's politics. Being trans is no guarantee of virtue.) In this instance, though, I thought that the inclusion of the asterisks could have no import other than a sneering implication that there was something phony, or maybe downright evil, about Manning's gender identity. I concluded that this particular attack on her embodied transphobia.

As a straight cisgender man, I admit my lack of personal expertise on the subject. I'd be grateful to hear the reactions of people who are closer to the front lines of these battles. Was I overreacting?