Is being judgemental and having a moral relation to his subject are essential criteria for a writer

Today is the death anniversary of Guy de Maupassant, and he died on 6th July 1893.  I recently sought about French writer Guy de Maupassant, and there were few articles regarding his life available which are depicted in depth. Among the books was there GUY DE MAUPPSANT; A BIOGRAPHICAL STUDY BY Ernest Augustus Boyd. Boyed was born in Dublin and he has written this book after much research, mostly he has gone through the Mauppsant letter to his family, friends and Gustave Flaubert. Flaubert was Msuppsant’s mentor and he was Mauppsant’s mother's friend. Mauppsant wrote poems, and it was flaubert who motivated him towards fiction, the budding artist wrote continuously for ten years and submitted to gustave. His weekly visits to the literary friend circle at Gustave’s house composed of Zola, Turgnev, and Flauvert helped him much more. They saw the merit , Turgnev was also in this friendship group and he gave Mauppsant’s writings to Tolstoy. 

One Thing attracted me abouty Gustav, who said "maybe it is monarchy, democracy, anarchy,  the government’s official aestheticism remains unchanged."

Brander Matthews writes—

In every work of art there are at least four elements, which we may separate if we wish to consider each of them in turn. First of all, there is the technic of the author, his craftsmanship, his mastery of the tools of his trade; and by almost universal consent Maupassant is held to be one of the master craftsmen of the short-story. Second, there is the amount of observation of life which the author reveals; and here again Maupassant takes rank among the leaders, altho the sphere in which he observed had its marked limitations and its obvious exclusions. Thirdly, there is the underlying and informing imagination which invents and relates and sustains; and there is no disputing the vigor of Maupassant’s imagination, altho it was not lofty and altho it lacked variety. Finally, there is always to be taken into account what one may term the author’s philosophy of life, his attitude toward the common problems of humanity; and here it is that Maupassant is most lacking, — for his opinions are negligible and his attempts at intellectual speculation are of slight value. Technic can be acquired; and Maupassant had studied at the feet of that master technician Flaubert. Observation can be trained; and Maupassant had deliberately developed his power of vision. Imagination may be stimulated by constant endeavor to a higher achievement; and Maupassant’s ambitions were ever tending upward. Philosophy, however, is dependent upon the sum total of a man’s faculties, upon his training, upon his temperament, upon the essential elements of his character; and Maupassant was not a sound thinker, and his attitude toward life is not that by which he can best withstand the adverse criticism of posterity. Primarily, he was not a thinker any more than Hugo was a thinker, or Dickens. He was only an artist — an artist in fiction; and an artist is not called upon to be a thinker, altho the supreme artists seem nearly all of them to have been men of real intellectual force.

Tostoy also says, three things are important for being a great writer

‘(1) a moral relation of the author to his subject; (2) clearness of expression, or beauty of form, — the two are identical; and (3) sincerity, that is, a sincere feeling of love or hatred of what the artist depicts. Of these three, Maupassant possessed only the two last and was quite lacking in the first. He had not correct, that is a moral relation to the subjects depicted.’

I think it could be a point, but morality is a relative term, Tolstoy saw it through his obsessive vision for morality. Tolstoy’s morality is still dumb before the question marks, his wife Sofia has asked in her diary. 

Is being judgemental, opinion maker and moral relation to his subject is important criteria for a great writer? I would like to hear others' opinions.

Dr Pragya Suman