What became the new teachings of the Mahayana sect that became popular and appealing to common people?
You're thinking original pure Buddhism, much like Theravada, vs new populist Mahayana Buddhism degrading and making up new teachings contrary to Buddha's teaching appealing to the masses, or some such. That's not the way it happened
Buddhism co-evolved in India in two separate areas into two separate ways of viewing Buddha's teachings. At some point around 2nd century BCE there was a complete disjunction
Nonetheless, the scriptures of both Theravada and Mahayana more or less initially appeared about the same time. Neither can claim being the earliest. They have a few scriptures in common, and none of their teachings contradict each other. In fact, Mahayana accepts the teachings of the Theravada, but until quite recently, Theravada rejected the teachings of Mahayana. Currently, with worldwide communication, they are putting aside differences and accepting each other more and more
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What became the new teachings of the Mahayana sect that became popular and appealing to common people?
You're thinking original pure Buddhism, much like Theravada, vs new populist Mahayana Buddhism degrading and making up new teachings contrary to Buddha's teaching appealing to the masses, or some such. That's not the way it happened
Buddhism co-evolved in India in two separate areas into two separate ways of viewing Buddha's teachings. At some point around 2nd century BCE there was a complete disjunction
Nonetheless, the scriptures of both Theravada and Mahayana more or less initially appeared about the same time. Neither can claim being the earliest. They have a few scriptures in common, and none of their teachings contradict each other. In fact, Mahayana accepts the teachings of the Theravada, but until quite recently, Theravada rejected the teachings of Mahayana. Currently, with worldwide communication, they are putting aside differences and accepting each other more and more