..“babysitting” the cadets.. And the Captain won't be babysitting a new recruit out of GA?
I don't think you can generalise by saying the crews doing the babysitting are 'unsuitable for employment' with QF. Obviously QF think highly enough of the operation, and their people, to place the cadets there in the first place.
However, with the large number of pilots available to the major airlines, they can pick and choose whom they consider the best of the best. This unfortunately means a lot of good and skilled people will miss out.
Difficult to be asked to help someone into the career you have missed out on yourself. But as professional pilots, we are required to pass on our experience to those 'entrusted in our care'.
As for a cadet taking the position of another pilot. True. But the cadet won't be joining QF for 2 years. In that time, QF are taking on other pilots directly. Everyone gets to move up the chain somewhere. The cadets will not get commands during their time with the regionals. Therefore the regionals will always have to recruit wisely to ensure they have a pool of experience available for promotion.