This quotation from 1984 illustrates the condition of the proles throughout the world.

Wherever they are, theirs is a life of grinding toil, endless childbearing, and poverty. And yet they still sing; they still have a spark of humanity in them that simply isn't shared by their rulers. That's what Winston means when he says that the Party doesn't sing; it has no humanity.

It is because the proles still sing, still live as humans, because they haven't been turned into brainwashed automata, that Winston thinks that they are the last hope left for overthrowing the Party's tyrannical rule and ushering in a new era of freedom.

The proles may lead a hardworking life, but they're still recognizably human all the same. It's because of this that the future belongs to them and to the race of "conscious beings" that will one day spring from them.

As for Winston and Julia, they are politically dead. Even so, they can still share in the proles' potentially bright, shining future so long as they can keep their minds alive the way that the proles keep their bodies alive.