The article does says so, despite its misleading sensationalist title:
The true novelty of the current paper is in biosynthesis -- the ability of the bacterium to make the new amino acid by itself, as opposed to being fed an unnatural amino acid from an outside source.
The questions asked at the beginning are the stuff asked 40 years at the RNA Tie club and the like.
James Watson has a new book out. I'm sure there are other books that go over those times and the ideas.