It’s always been an issue in Commonwealth forces - there are plenty of competent people, but there are others who got there because of other factors. I think I was competent, but my own career certainly benefitted from having gone to ‘the right school’.
And back in the Second World War, there was still the issue of British officers sometimes being seen as superior to those from the Dominions - Muirhead-Gould is a prime example - he jumped from being a Commander in the RN to being put in command of mostly RAN forces as a Rear Admiral in a matter of months. From what I know of him, he was an able administrator and while Sydney Harbour was still a port on the other side of the world from heavy fighting, he might have been all right but once the war started in the Pacific, it was a completely different and he wasn’t up to it.
In the Army, they were called "ring knockers" for wearing their academy ring prominently.
But, most US professional officers are competent.
I never met a colonel that wasn't fairly bright, and all general officers I met impressed me as being quite intelligent.
Of course, just having intelligence is not the same as competence.