Of course this is happening and going to keep happening.
People upgrading now have joined CX and had a lucky run on the long haul fleet their entire career, without any prior experience, being upgraded to heavy jet long haul Captain with approx 200 or so actual landings under their belts!!
This could all be alleviated by putting all crew through a Junior (regional) fleet then onto Senior (long haul) fleet programme. Let the young keen ones flog around Asia and ME, getting lots of sectors, lots of great exposure to all sorts of situations, and allow them to grow into experienced old buggers who then deserve to have the nice Senior fleet job.
It has always made sense in other airlines to do it this way. For a good reason. Also keep the troops happy.