It seems pretty clear to me, especially with the context provided in the article itself: don't judge an artist solely by the last thing they made; don't write them off just because they're going through a bad patch.
So while an artist should be allowed to have down periods, it also shouldn't be surprising if people move on. We're not looking for needles in haystacks anymore, we're looking for needles in a stack of needles. There may be value in coveting needles and hay from a particular artist, but that's an intensely personal decision to make.
1) A suggestion is made for the readers and to the society to change how the judge and think about artists.
2) Writers tries to convey new norms, forbid judgement.
What do you think the writer tried to do here?