I do believe that the core beliefs preached by the historic Buddha and recorded by his followers into sutras and other scriptures were, in part, a reaction to the Vedic beliefs and rituals dominant in South Asia.   Firstly the Vedic literature taught non violence, to form his religion Buddha agreed upon non violence and decided to take it one step forward and he saved the (scarified soon) animals from being killed and saved the people from being further misled by the corrupt priests.  Buddha also taught four basic truths that suffering exists, there is a cause for suffering, suffering can be eradicated, and there is a means to end all suffering.  These truths became popular in the Buddhism religion but these four noble truths had previously been discussed in the Sankhya philosophy before Buddha's appearance, and had later been further elaborated upon in Patanjali's Yoga Sutras. So this train of thought actually was not new.  “Buddha also taught that suffering is essentially caused by ignorance and our own mental confusion about the purpose life. The suffering we experience can end once we rid ourselves of this confusion through the path of personal development. Otherwise, this confusion and ignorance causes us to perform unwanted activities that become part of our karma that must be endured in this or another existence.  Although this was the basic premise from which Buddha taught, this theory was mentioned in the Nasadiya-sukta of the Rig-veda long before Buddha ever appeared.”   Many other parts of Buddhism have seemed to come from the Vedic beliefs and rituals.

I agree with the statement that Buddhism has changed over time.  I believe that Buddhism has lost focused of the original main focus which is to reach enlightenment.  People began to put their own twist on the religion.  Schools also emerged having to do with the Buddhist religion, but instead of focusing on the whole religion these schools focused on one specific part The two most prominent schools were the Ch'an and the Pure Land schools. The Ch'an school emphasized the practice of meditation as the direct way of gaining insight and experiencing Enlightenment in this very life. The Pure Land school centres its practices on the recitation of the name of Amitabha Buddha.  I do not think that today Buddha would recognize or be pleased with what his religion has became.