Why did not they promote those improvements, discussions and interests in the core?
Well, for one thing, any discussion of ideas that deviate from Core's established roadmap are deleted out of existence in all the discussion venues that matter.
For another thing, Core is already irredeemably tainted by the segwit trojan.
You must be new here.
And you completely misunderstood the point this guy was making in your rush to condescend to him with your idiotic rhetoric.