Is the Tathagata 'special'? Mahayana or Theravada, or any other offshoot. Is a Buddha an exception? Or a personification?
It is not personification. There is evidence that Gotama Buddha exists in India. He is special so he was called Samma Sambuddha.
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when the Buddha is designated a sammā Sambuddha, &quot;a perfectly enlightened one,&quot; this highlights not only the fullness of his enlightenment but his authority and reliability as a spiritual teacher.
https://www.accesstoinsight.org/lib/authors/bodhi/arahantsbodhisattvas.html