It's been my experience that PoC is used by the same white cis people who will bitch at you if you don't put an asterisk after "trans". It makes them feel like special snowflakes to absolve their white, cis tumblr-guilt in this manner instead of, you know, doing actual helpful things for other communities.
Finally, someone who sees how meaningless the asterisk is. There is a reason I lampoon it, because it's far more harmful than helpful. The only two reasons I've heard for the asterisk are pathetic: (1) "we put the star on 'trans' to draw attention to ourselves and our struggles", and (2) "it is (somehow) more inclusive." The first one was said by a transwoman I have little respect for. But the "inclusiveness" argument just irks me. We already have an umbrella term, "transgender." A person choosing to live as the other gender is a "transsexual" a person who displays quality of both are "bi-gendered." A person just enjoying to dress as the other gender on occasion is a "cross-dresser," a "transvestite," or a "drag-king/queen" (avoid transvestite though, has more negative connotations, but some prefer it). People who choose not to confine themselves to gender are "genderqueer" and people who choose to not play into gender at all are "agendered" or as some prefer "genderfuck."
So, we already have a term that has been around for 35 years that does what "trans*" seeks to do. But then what about the other implication, that it makes such terms as "trans" or "transgender" exclusive and discriminatory? The contrapositive to "'trans*' is more inclusive" is that "'Trans' is discriminatory." And that bothers me because now, you're taking a group who already has a shit ton of social problems and throwing a bigot on them just because they don't see the awesomeness of the asterisk. I seriously think it was made up by a troll who did not have our best interests in mind.
Finally, the only real difference I've seen in usage between "trans*" and "trans" is that people include the asterisk if they're not trying to look offensive. At most, it's placating, but does nothing to solve any problems.