It was messed up already before Dubas got there. They've only made two first round picks in the last eight years... before this trade. Their prospect pool is clearly bottom five in the league already... so trading away one more first and second didn't really do much more than was already done.
and yes, they will be an absolutely terrible team as soon as Crosby and Malkin are done. But, they really don't have much in the way of assets that would assist with a rebuild, if they traded them... and clearly Crosby, Malkin and Letang want to stay... so, only choice is to try one last time.
Pittsburgh certainly has had financial issues when they haven't iced a competitive team, but the NHL has kept Arizona afloat for how long... can't see them letting Pittsburgh fold.