Unless there is a clear conflict of interest, such as an "expert" urging a particular course of action which aligns to benefit their employers, then the audience should probably just engage their critical thinking a bit more.
The majority of UK experts will probably have opinions that align with UK ethics/morality/society and urge options that benefit the UK state and it's allies. I would assume that would be an absolute given too.
When I watch Chinese citizens give their expertise on matters, I know that it will probably align with the Chinese state and benefit them (as opposed to strictly the UK state). Have people lost all of their critical thinking skills?
That's exactly the issue
How is an General Everard being a patron of an armed forces charity, a software company enhancing onboarding experiences, a skills training company or even an "informal network of strategic thinkers" who write blogs likely to influence his defence spending views more than being a general?
It's not like it's standard journalistic practice to provide the entire resume of any other type of commentator.
Presenting them merely as experts because they are "former X" creates a false impression of impartiality.