“It seems more likely that He claimed to be the True Rabbi just like He said He was the True Vine and the Good Shepherd and the Only Way to the Father. Everyone else was pretending; He actually was what others could only claim to be.”
Can’t disagree with this.
And then again, what did it mean to be officially trained as a Rabbi then? Particularly with the competing sects of the day. It's not like it was just between the Pharisees and the Sadducees. There were also the Essenes and the Zealots. Some would say the Herodians were a sect (I say it might be best to treat them like more of a political party than a sect).
I bet if someone you were to go back in time and ask one of any of those sects' leaders if leaders in the other sects were Rabbis, you might start a fight.