Its pretty imminent with the A350ULR, 787 and 777X making the stopover unnecessary. The verdict is in and people just prefer to get it done and over with minus the gharish shopping experience at DXB or wherever. If you can fly SYD-LHR that basically is it. The only frontier after that is antipodes, which there are not too many of. Basically just Asia to South America and New Zealand to Europe. Neither are really convenient for middle east connections (connecting through North America is preferable for NZ to UK) nor particularly lucrative.
Slowly but surely flag carriers are just going push out Qatar, Turkish, Emirates, Etihad route by route. In a vacuum losing SYD-LHR isn't the end of the world, but it'll be more than that. Soon after that it'll be India to North America, then Europe to more Oceanic and SEA destinations like BKK, MEL, MNL etc. Singapore and Cathay will hurt a little too, but HK and Singapore are actual destinations in their own right, which gives them at least something to fall back on.
I mean in the end it doesn't matter to Boeing or Airbus. The aircraft will still need to be bought, it just wont be the usual big widebody buyers. Think massive expansions to the fleet of Qantas, BA, United, AA, Lufthansa, Air NZ, Thai, JAL, ANA and the Chinese carriers. Long-term those are your big winners in all this.