I'd say that Neuromancer, though it is not commonly regarded as a political novel, is more useful as a metaphor, given it predicts the explosion of players and political complexity created by the inability of any one group to exercise control over technology, which is a theme pretty much absent from 1984.

As to whether the political novel is dead, it is always kicking about in science fiction, where fashions have their own undercurrents that are much less subject to the whims of what can be regarded as literature. Science fiction, probably to its benefit, being rarely regarded as literature in the first place.