I was always taught that the Oral Torah was taught by Hashem to Moshe on Mount Sinai, and that the Oral Torah is the Mishna, but any time I open a Mishna, it’s nothing about what Hashem taught Moshe definitively, etc., It’s always “Rav __ says X, but Rav __ says Y.”
Why do we call Mishna the Oral Torah in light of that?
Further, why do we care what this rabbi claims is the halacha, or what that rabbi claims is the halacha? Shouldn’t we just care about what Hashem said was the halacha?
Serious question. It makes no sense to me.