I've already stated that it sucks for low levels to fight against level 50s. I'm not disputing that. If they separate the 50s into their own bracket though, queues will get much worse for them. It's lose-lose. They make brackets and queues will grow exponentially; they leave it as is, and the lowbies will complain. However, the lowbies won't be lowbies forever, and most rational people will realize that they shouldn't base their PvP experience off of their early levels.
Plus, you're automatically assuming that whenever a lowbie queues, they won't be matched up with any 50s on their own side. From my experience, it's usually balanced out, with each side having their fair share of low-levels and 50s. So no, just because you face 50s, it does not automatically follow that you have virtually no chance of winning whenever you queue.