Heck, I don't know why. I just never find myself using the term 'yaoi' anymore, unless it's a DMP yaoi manga, which I almost never read anymore because I haven't read a good one since Jazz ended. They all seem the same now.
Also, if it's anime or manga, then it's yaoi or shounen-ai. If it's not anime or manga, it's slash.
So yes. The term 'Star Trek yaoi' makes my eye twitch a bit.