In the pocket
You say "allegedly in the pocket of the airline". I must correct you (with humble apologies): They are evidently in the pockets of the airlines and manufacturers - it is where all the money comes from to pay for the swish restaurant that we mere pilots are no longer allowed to use because we commented on how brilliant and cheap it was...
The XAA is now an "agency" or "trust" if you care to misuse that word. It operates at nil cost to government, and gets a free hand as a quid pro quo. The unintended consequence of this is that the XAA cannot rock the boat as it would be killing the goose that is laying their golden egg. All very cosy...