"Ex UK military members discover the private sector pays 10-20x more" underlines the title, but yes, media should disclose it. But even if they were "just" retired ex-military, their bias would be the same (being a member of the UK military).
10-20× more in private sector for senior leadership/advisory role sounds reasonable, but still, I wonder if some part of that compensation stems from the fact that the person is availing him/herself as an asset of influence, i.e. can be used to push narrative through media while posing as independent, credible expert. Needs further research and/or A/B testing I guess.
Media in general is poor on declaring any and all bias of their various interviewed "experts".
Quack doctors spruiking amazing new treatments (that they hold shares in).
Automotive experts promoting car brands (that they receive advertising and influencer dollars for).
etc.