The reason is very simple, they never intentionally concealed these things.
Among the cultivators of high realms, this is common knowledge.
As for the possibility of leaking secrets and bringing about negative consequences?
With a heritage spanning ten thousand years and profound mysteries, does listening alone enable one to find flaws?
Telling you that the strength of Dragon Elephant Body Cultivation lies in its Vajra Indestructibility yet you still can't do anything about it, can you?
Telling you that Sword Sect sword cultivators are strong in their invincible offense and swift speed but have fragile physical bodies, yet when you encounter a Sword Sect sword cultivator, aren't you still bound to die?
This is the grand path, forthright and upright.
Only those minor sects and factions that pursue crooked practices, such as cultivators of the so-called Blood Gu Technique, whose combat power plummets in daylight, go to great lengths to conceal their secret arts.
