Most of the saints and sages of the past are mostly social reformers, thus they were more concerned to the humanism rather than the truth

Most of the saints and sages of the past are mostly social reformers, thus they were  more concerned to the humanism rather than the truth. Their contribution is very valuable to live in the practical world.  But their contribution is not the means for acquire Self-Knowledge or Brahma Gnana or Atma Gnana.   Thus humanism is part and parcel of the universe, which is mere illusion.

That is why Swami Vivekananda said: - “You have to grow from the inside out. None can teach you, none can make you spiritual. There is no other teacher but your own soul.”

Mundaka Upanishad:-

Ignorant fools, regarding sacrifices and humanitarian works as the highest, do not know any higher good. Having enjoyed their reward on the heights of heaven, gained by good works, they enter again this world or a lower one. (First Mundaka -10-   Chapter I [Source: "the upanishads - a new translation" by swami nikhilananda in four volumes)

The humanism is limited to practical life within the practical world.    The path of love is path for humanity therefore, it is individualized path. Thus path of love is limited to the physical structure, it cannot transport one to ultimate end.  Thus seeker has to understand the fact that the practical life and practical world are part of the mirage from the ultimate standpoint. 

The simple reason is that the average person may have desire for knowledge but when the whole society is immersed in belief system and feeling himself   out of place because of societal fear and surroundings circumstances and he thinks it unfits him to pursue the path of truth. 

That is why Buddha said:-  

Do not believe a spiritual teaching just because:-

1. it is repeatedly recited,
2. it is written in a scripture,
3. it was handed from guru to disciple,
4. everyone around you believes it,
5. it has supernatural qualities,
6. it fits my beliefs anyway,
7. it sounds rational to me,
8. it is taught by a respectable person,
9. it was said to be the truth by the teacher,
10. one must defend it or fight for it.

However, only when it agrees with your experience and reason, and when it is conducive to the good and gain of oneself and all others, then one should accept the teachings, and live up to them."
....Buddha.

The seeker of truth is one who is ready verify and has courage to accept and reject the truth when he finds out what is truth and what is untruth. The meek will stick to their inherited conditioning remain experiencing duality as reality.