Globaliser

Plus LAX-JFK is a premium route in its own right. So that suggests that if you want to include people who are going to do a 2-stop trip, LAX and NYC are likely to be good candidates for that.

A non-stop would also run into the same problem as all of the ultra-long haul operations running and talked about: the cost of fuel. It's not so much what the aircraft could theoretically do, but how much fuel you need to burn just to carry the fuel you need to fly the last chunk of the flight. If you load an tonne of fuel at SYD, there's only about half a tonne left by the time you get to LAX, simply because you've burned that much to carry it that far. It gets progressively worse as the flight gets longer.