The thing about that... Is that whether or not something registers as cool or not generally needs to come from the group. As an example you could try to "take back" an n-slur from bigoted use ... but if that initiative isn't coming from the community to whom that term is levied you are basically just using an n-slur because you believe yourself entitled to use the slur for your own personal reasons.
It's not just about sticking it to the Conservatives, it's about listening to the why that comes from a community that is often talked about rather than talked directly to... At best trans people who hear you are going to think you are out completely of touch like people who pronounce pokemon like "Poh-key-man"... Or that you cannot be counted on to listen, that you are a different kind if problem and you are someone to hide from being openly trans around if they can because it's ultimately safer than rolling the dice against whether you are a transphobe or not. Places (for example a work place) where terms like "transgenders" is openly used without challenge from other people is a message to us that that community is either not safe or at least very very ignorant... And that self advocating in that environment is going to be an uphill struggle of dealing with people who are convinced they know what's best for us more than we do...