Have you written to you union reps, your safety manager, and of course, The Authority, and CHIRP?
Pprune is great place to let off steam, and find sympathy and support but is not a place to get official action. Whistle blowing is a scary thing to do, but is often necessary.
I speak as an experienced FO who is being passed over in favour of youngsters with deep pockets. Good luck with getting your point heard.