There's this huge movement in online spaces lately to bash any and all positions and opinions by calling them transphobic.
Vote right? Transphobic. Vote left? Transphobic. Abstain from voting? Transphobic. Support a company? Transphobic. Boycott a company? Transphobic. Indifferent about a company? Transphobic.
The simplest explanation is a bunch of right-wingers are trying to make the term meaningless. Anyway, nowadays when I hear someone is transphobic, I make sure to wait for solid evidence before changing my opinions.