I think Selina and the team's treatment of Amy thus far is mostly about needing a scapegoat. When Mike was part of the team he fucked up enough that blaming him for problems seemed reasonable, and of course Jonah always good for releasing some steam. Without them things fall to Amy, less because she's a fuck up, and more because she's the one who will try and get Selina et all to be a little introspective and change, when they really just want to blame someone else.
They’re bullies, in other words, and they follow the leader in the hope that if they fall in with her abuse, they won’t become victims themselves.
Which actually, doesn’t bother me – if I needed characters I enjoy to be admirable people I wouldn’t enjoy Veep at all – but the execution is shoddy.
Because if that IS what’s going on, it would be a lot easier to recognise if Selina hadn’t been attacking Amy in explicitly gendered terms since at least the middle of season 5. So, it’s not new – or, at least, not new enough to be easily recognisable as the dynamic you’re describing. There should be a more obvious ramp-up in the abuse – the problem is that there can’t be, because the show’s had the characters interacting with such unrelenting vitriol for so long, that there’s no where to ramp up too.
That said, I think you’re right that that is what is intended – I find it noteworthy that Ben explicitly asks Amy for a copy of her campaign post-mortem, for instance. (It’s also one of the few remaining signs of Selina’s political competence that she assigns that task to someone who she knows will tell her the unpalatable truth, even if she refuses to listen to them).
What is more interesting to consider is who will become the designated victim once Amy is gone, though my money would be on Dan – Kent and Ben will stick up for each other over him. (Another reason why he shouldn’t drive Amy away from him, because, outside of exceptional circumstances, she would be loyal to him).