OK, so I made a thread about this a few months ago.
IMO, this whole pronoun thing is hypocritical. People who go by "they" are basically saying, "I don't fit all the stereotypes of my gender, therefore I am not a member of that gender." This stance only reinforces gender stereotypes, which are, IMO, irrelevant in today's society. I don't understand why people need to use a different pronoun rather than embrace the fact that a male having effeminate qualities (or vice versa) is completely normal and acceptable.
When it comes to trans people, it's different. Sylvie, for example, actually puts in some work into coming off as the opposite gender. I'd have no problem calling Sylvie "she." Someone who is clearly a member of their original gender, but insists on going by "they" or the opposite gendered pronoun, is looking for drama or trying to be part of some movement just for the sake of it.
Also, "they" is plural, end of story.