I don't see anything wrong with them. They are there, all players can get them if they really want them bad enough, as TseTsuo said.
I'm new to the game, I've only played in WSG every now and again while running through IF. I think I may have played WSG probably about 15 times tops, I've played with and against "twinks".
I really don't see anything wrong with them. Yes they kill me quick. But you know what, I respawn in under 30 seconds go out and try again. They aren't unstopable, I've even killed a few myself. I was even fortunate enough to go 1 on 1 against a twinked undead warlock and win (yeah it was pure luck though, I think I hit shield bash the same time he was casting fear, so I think that threw him way off giving me the win, I know it was lucky since I thought I was spamming the mocking blow button, the victory was short lived though I was stabbed in the back by a sneaked rogue) Anyway, the point is that they are beatable, it may be a little harder to defeat them, but it's not impossible.
The biggest trend I see is people giving up. I actually was grouped with someone who remained dead through the whole game because there were twinked horde. The whole time he was whining about them being twinked and how it was rediculous, and they should just end the match. I think he spent more time crying about the twinks then he did playing the game.
Anyway, this is a huge generalization but, it seems to me the people who complain about the twinks are the people who play in the battlefields only to get that epic gear, and not for the fun of playing against other players.
If it makes you that upset though, then just go do something else. People forget this is a game, and games aren't meant to frustrate you and drive you crazy, they are there to help you relax and get away from the hussle and bussle of daily life. So if it gets you that aggrivated, go do something else, it just isn't worth it to get so upset about something that really isn't that big of a deal.