I guess from the fact that they have updated their website, we can infer that they are thinking about some kind of extension - and the idea hasn't simply been forgotten
I think for Manchester passengers, even Manchester Airport would be better than Crewe because if you're travelling on an LNWR/Northern only ticket, Manchester Airport gives you much better options for getting into Manchester than Crewe does, with its one very slow Northern tph. And it would give a lot of communities South of Crewe a new direct connection to Manchester Airport.
And I for one will be very happy because I often go London to Lancaster or Windermere. And if LNWR run through to Manchester Airport, that would mean I can use a cheap LNWR ticket to get to Manchester Airport and then pick up a direct train to Windermere from there