In the good old days, everyone had been through the same selection process, which usually involved some personality testing. In short, everyone had "the right stuff". These days it's all about the ability to pay. More research to do i think!
Depends how far back you are looking, PP.
Judging by your age, when you were training the cheque book was king.
The selection process has improved considerably since then and includes some of the most advanced physchometric testing techniques currently available. With reputable schools accruing a percentage of their profits in order to afford to offer a 'skills guarantee' i.e. a refund if you don't cut the mustard, it is more than ever in the school's interest to make the assessment process as thorough as possible.
There are of course less reputable integrated training schools out there who will sign anyone up and refuse to offer any form of skills guarantee. T'was ever such.
Concerning the argument as to whether these MPL graduates will make good captains, time will tell, but my hunch is that they will prove their worth.
Feel free to lambast me when the first MPL graduate turned captain proves otherwise.