These teachings are not clearly observed by the people(who called themselves - disciples) - and they change from previous attachment to this new attachment. On this attachment - they got pride,money,fame,satisfaction,‘business’,etc… So, this does/will not stop - whoever ‘K,a,b,c,d’ says - until each & everyone observes the actuality.
In-depth observation of sufferings.
As per Gautama’s history, he was once a prince. Astrologers predicted that the King’s son - may become a big king or spiritual teacher(sankhya). Hearing this king - gave all comfort to the prince and kept him within the castle. One day he escaped the castle - and found every people he met was starving(suffering) to death. So he renounced that life - and went to a forest - to observe within - why this all happens. Then “Bang” - everything vanished psychologically. You may have seen his/‘Buddha’ sayings - are mostly based on desires,sufferings. So many scholars cling to those words - compare it with K’s & proclaimed that K is a ‘buddhist’.
The same happened to Rama too. In India - once a prince learned all the scriptures - he has to visit many kingdom’s to learn the actuality. After seeing all this(sufferings until death) - he returned back to kingdom - and hadn’t ate much. The King(Dasaratha) found his position much worse. Then the history says - Vashista - a sage - teached Rama - the actuality of this Universe(outer) and Brahman(inner) - which is called ‘Yoga Vashista’.
Many Sages - had written down their observations of that ‘Infinity’ - and explained them to people. But they(disciples) formed a sect - called Advaita Vedanta, and became a scholar - in those writtings(Upanishads) & the business goes on. Here noteworthy is - Ramakrishna & Swami Vivekananda is an exceptions from all the Vedantists. They too observed and expressed their opinions - and are against the ideals/way. (If you have time - just read “Practical Vedanta” of Vivekananda, not as a disciple, but as a story/history).
In case of K - he was teached about Bible,yoga - in Theosophical Society. But it’s of no use, when his brother(who he is much attached to) died - he couldn’t come out from the pain. He observed the actuality. Then “Evanesco” - everything vanished psychologically.
At last - what remains there - which has neither birth or death is the ‘Love,Compassion,The One,Truth,Permanent,Unlimited,God,Conscuiousness,Emptyness,Brahman,etc…’ which cannot be expressed in words - and can only be felt.