Why theravada buddhism is called heenayana/lesser vehicle when it was followed by buddha himself?
The Buddha was not a “follower” of Hinayana Buddhism. The Hinayana tradition appeared several hundred years after the Buddha’s death. The Buddha repeatedly said that he only taught “the fact of suffering and the cessation of suffering.” This fundamental teaching is common to all forms of Buddhism. I believe that it’s very important for modern-day Buddhists not to get tangled up in the polemical wars about “correct” Buddhism. These wars began over 2,000 years ago and have nothing to do with awakening. The Buddha was only concerned with awakening, not in establishing a correct doctrine. That should also be our concern.