I am not sure it is good to comment on any Master especially one who has followed a very different line. From whatever little I have read and heard of him, he seems to me to be in line of the Buddhists Tantra of the left hand path. I am not sure about what kind of new world he spoke about but surely a world-negating thought that speaks of an ultimate Nothingness as the foundation of creation certainly does not go well with the idea of a New world. Of course the thought of a New World did catch the ears of the previous century but most of them were either a rehash of the old and based on some kind of spiritual experience leading to altered states or else a kind of humanity living in higher states of consciousness or perhaps even as Jivanmuktas. Still others, who are best not named, used it as a euphemism to draw disciples often giving to the word a totally twisted sense. To go into all that is neither desirable nor necessary.
All that I can say is that what Sri Aurobindo brings is none of these old wines in a new bottle. His idea of a New world is based on a very sound practical footing. What it means is that as long as human nature remains what it is there is little chance of a new world that can endure the rub and change of time and the popping up of the human ego that pursues man right up to even the domain of the gods. While self-realisation, provided it is genuine and not one of those quasi enlightenment fancies, can free us from the ego yet the field of nature remains the same, imperfect as ever keeping us tied to the gunas when we act. It means a state of inner freedom of the soul of the spiritual element within us but nature would continue to act under the principle of the three gunas. This is as far as spiritual evolution has gone for man. the highest is embodied in the Gita wherein the liberated man sees the Divine everywhere and yet engages in action of every kind including the most fierce.
Sri Aurobindo and the Mother had realized the highest state of the Gita as well as the Buddhist shunyam besides many other realisations. If this still did not satisfy them it is because this was not enough to transform humanity or bring down a diviner world into our present ignorance ridden one. Nothing short of the divinization of life, a transformation of the mind into a perfect luminous channel of infinite Truth and a plenary supramental illumination, of heart into a perfect vessel of divine love and beauty and ananda, of life into a luminous force driven no more buy the straining hooves of desire but the self sure perfect movements of the Infinite Shakti, of the very body into a translucent mantle of the Divine, his perfect temple and abode would satisfy them. They not only saw its possibility but told that the hour is now.
Another interesting thing is that Sri Aurobindo and the Mother saw the extreme difficulty of this endeavor and did not bother to draw disciples by false promises or rainbow hopes. Nor did they try to entice man through popular series of books readily available on cheap book stalls that stimulate and titillate some shallow intellect as those of Osho do. This at least has been my experience with his books. I found them extremely superficial though cloaked in the language appealing to a kind of intellect that spares itself the trouble of original thought and hence is easily enticed by this kind of reasoning that hardly draws upon facts and is more like catch phrases that give the mind a kind of shock and while it is recovering its sanity it allows enough room for all kinds of suggestions to enter.
This is my personal opinion, but of course there are always those who will find in him the Master who will lead them into the new world and have faith in his teachings. However, it will be a sort of paradox since Rajnish was above all an iconoclast of a certain kind who demolished more than he ever built. In this respect he deserves his place among the line of spiritual masters who came to destroy the old world order, especially the structured fixed dogmas of formal religion. But destroying is one thing and building a new world is quite another. I do not think he had the know-how or the power or even the vision of what the new world would be or could be if at all he ever mentioned it, at least as far as I am aware of.