A (further?) chance to display my ignorance here and I have no intention of causing offence.
'When I was a lad' 20 years ago, about 10-15% of the population did a degree-level course. Young graduates, as opposed to those taking degree the hard way (OU etc) later in life, wanting a military career usually sought commissions; some were up to the mark and some were not and selection/training system sorted that out with some degree of success. There were plenty of high-quality non-graduates, who just didn't want to spend another 3-4 years in education, who also were commissioned, became NCA or joined the trades, and lots subsequently obtained degrees (the hard way).
In a few years, the Government plans to have 50% of school leavers go on to tertiary education. I would have imagined that the majority of the RAF would come from people in this 'top half' even given that some people just dont get on with 'academics'. Are young people with a degree wanting to become NCA or join demanding trades? If not, where are we going to get the right sort of people?