Discrimination
The UK MOD has Nationality requirements which restrict non Brits from joining the armed forces. They are able to do this under the cloak of crown immunity.
The UK MOD until recently restricted the employment of homosexual people and also until recently the employment of women in many job categories.
Under the cover of Crown Imunity the MOD was able to drive a bus through UK anti discrimination legislation.
Now airlines do not enjoy Crown Immunity. By biasing recruitment policies towards service applicants the airlines may inadevertantly be indirectly discriminating against non British people with the right to live and work in the UK, discriminating against homosexual people and also discriminating against women.
Now im not playing any cards here just pointing out what may be an interpretation of employment law and it is surely the right to live in a free and fair society regulated by democratic law that the military should be serving to protect.
The notion that by positively seeking applicants from the armed forces airlines are seeking highly motivated, disciplined and capable candidates overlooks the fact that all the above qualities are required by any commercial pilot be they a flying instructor, air taxi pilot, turbo prop pilot or jet pilot. Those qualities of motivation , discipline and capability are required by all aviators and are not something that the MOD has a monoploy over.
While service pilots have had a standard of training second to none on leaving the services many are inexperianced, low houred and underqualified compared to pilots currently on the market.