I'd tend agree with the thread starter but to be honest Pprune is a very different place from when I joined in 96. The number of serving military users has decreased markedly over the last 5 years or so, due to a combination of thumbscrews from the military hierarchy along with the slow dilution of the interesting stuff with triv, rubbish and spottery.
Lots of the historical stuff is fascinating; the thread on life as WW2 pilot for example is gold dust. Sadly there is an equal amount that is just tenuous triv. The old adage of any forum is "if you don't like the subject, don't read the thread". That's all well and good but sadly most interesting/relevant subjects quickly vanish up their own cyber backsides as random people get involved adding more and more noise of ever decreasing relevance.
The Wg Cdr Spry thread, for example, should be a place to discuss current topics or good old "I learnt about flying" stories that inform and educate. It shouldn't be a place to air tired and tedious old hobby horses or to pick fault with the RAF hierarchy.
I'd agree that there is a place for historical & nostalgic military aviation chat but I think there is also a place for discussion of current military topics, drawing where necessary, on the mountains of retired experience out there.
Pprune is currently of little relevance to 90% of serving folk. A bit of demarcation might turn that around....