TwoOneFour
I think that the author probably meant that, whilst there were and still are hugely imaginative and inventive minds in Britain, it does not follow that these admirable traits are necessarily possessed by the majority of decision making or fund providing minds in Industry, Banking, Whitehall or Westminster, who would, if the post-war history of British aviation is any indicator, be the possessors of fudging, incompetent, malicious, complacent and ignorant ones: ie it's not all "Britons who are having the (bright) ideas in the first place".