I dont believe that argument.
They are two different entities.
The players strive for the premiership and hold it in very high regard. However when that dream ends each year they want that International honour just as much.
Are you telling us that those in contention who miss out on the WC squad next year won't be fazed as their eyes are on the 2018 premiership? Not a chance.
I reckon the hurt from playing in a losing GF would hurt a player far more than missing a World Cup squad
Recently The Roar had a thread on the greatest player never to win a GF. I immediately thought of Tommy Raudonikis. Based on your comments above happy, suppose we gave Tommy the choice of which he would prefer:
We ask him would he prefer to be the premier half-back of the 1970s and (usually) selected to play for Australia; or, to never have represented Australia (or NSW) but to have won a GF with the Magpies.
What do you think he would choose? Which achievement would give him most satisfaction?
I suggest representing Australia will have given him more satisfaction. After all, there are plenty of "neville nobodies" that have been part of a GF winning team, most of whom we have forgotten, but there are not many greats of the game. Tommy's representative record puts him firmly in that category and I think it is his representative record that he would take, given the choice.