The blessings are done. Jacob has said something hard or something heroic about each of his sons — one has lost the birthright, two have been scattered for their rage, one has been compared to a serpent, one to a vine, one to a lion. It would be easy to finish with a sigh. The Targum refuses. "All these Tribes of Israel are twelve: they are all righteous together, and this it is which their father spake to them, and blessed them; according to his blessing blessed be each man" (Genesis 49:28).
The Aramaic says something the Hebrew only implies: kulhon kachadha zakka'in — all of them, together, righteous. Not some. Not the favored. All twelve.
This is one of Judaism's most distinctive instincts. Israel is not a hierarchy of the deserving over the undeserving. Reuben, who fell, is still Israel. Shimon and Levi, who were scattered, are still Israel. Joseph, who ruled Egypt, and Benjamin, who would later host the Temple, are Israel alongside them. Each brother received a blessing fitted to his nature. None was erased.
This is why Jewish prayer includes all twelve tribes in the same breath — the priestly blessing, the Temple breastplate, the messianic hope. Jacob's final word is inclusion, and the Targum makes sure we hear it.