Didn't this already happened?
Mat 21:9 And the crowds that went before him and that followed him were shouting, "Hosanna to the Son of David! Blessed is he who comes in the name of the Lord! Hosanna in the highest!"
Matt 23:39...You shall see Me no more till you say, "Blessed is He who comes in the name of the LORD!' "
Jesus then left the temple and proceeded to teach the disciples about the Tribulation.
It seems clear that Jesus is not talking about a past event, as you pointed to in noting Matt. 21:9, but is pointing to when Israel will come to recognize Jesus as their Messiah and the Son of God. Supersessionism requires the complete separation of Israel from the LORD and the passage the author is quoting indicates that is not the case.