They're not dead just yet, the carrier remains US Airways.
As was quoted by another poster BA/AA have a massive number of flights from LHR, in the face of overwhelming competition MAN really does have to fight its corner.
In what terms? I'm sorry you're just ranting bagso. What are you fighting? What's "victory"? UK passengers can choose to fly MAN-LHR-xyz or MAN-US Legacy Hub-xyz, both options have good pricing. United and Delta also offer good options over LHR as so VS with Little Red. I assume you want Little Red closed so everyone has to fly over the US hub and connect there. Either way, the MAN-US market is not infinite. In terms of "much cheapness" connecting over LHR, those are the people you don't want flying on UA/US/AA/DL out of MAN as that sort of yield isn't matched by insane London prices down the front. You need to let the super price conscious customers connect over LHR, as that keeps the yield on MAN-US decent.