The answer is of course obvious. The establishment comprises those who are doing very well out of things as they are and want to keep it that way. Lucrative jobs, gongs, titles etc can be shared out amongst this in group with the occasional sop to a black comedian, woman or similar who pose no threat to the group as however good they are there will only ever be a disparate handful of them against the solid phalynx of hundreds of Old Etonians who so dominate our political, legal, business and other elites. Important jobs are always filed from within this in group. Knowledge or experience is not necessary.
The EU works a similar system thus ex social worker Baroness Frumpy became titular head of the EU Foreign Service but again there was only one of her so no matter how bright was ( and she was not) it was child's play for the EU crats to out manoeuvre and isolate her if she did not do as she was told.
It is strange then to see Cameron thrashing around today at the British Museum threatening us with WWIII if we do not vote as he tells us.