You can't blame people for not sustaining your fun when you don't bother respecting theres. If WB were handled by guilds they could eventually deal with the boss and some gankers but since it's full pug without any coordination it's not possible. If you want sustained fights you've got to take into consideration other peoples fun. If you don't, if for you it's all about stomping people go figure people log off instead of fighting.
When you're 19 vs 4 what's the point of fighting back ? You'll trash the 4 ****ers once or twice and then they'll go into hiding/mini before sneaking back around and killing a few weakling too far from raid.
Like it or not PvP needs to be consensual to some degree. You can nonetheless impose it to people... but if you want them to fight back you have to do it in such manner it doesn't feel one sided. Basicly take risks, be deliberatly exposed, try ambitious things. 9 out of 10 of the people ganking during WB focus on lowbie mages furthest away from raid. They gank them and run away in hide. If it's not a problem against an organised enough groupe, it is against pug and it's even worse on WB where everyone isn't in raid and red tags doesn't necessarly mean ennemy.