jerusalem" coming down to Earth
It is a heavenly entity and not part of the earth at that time. Jesus and the elite that make up the Messianic kingdom and rule from the heavens But the point of Jesus word trampling is Gentile ruling, until the appointment times of the nations when the kingdom was established in the heavens according to Rev which is the allusion in Luke. So, the Olivette refers to the destruction of Jerusalem which happened in 70 and to the end of Gentile Times. If you don’t want to believe that happened in 1914, ok but the Parousia is connected to the end of the Gentile times.
Judaism rejects the Greek Scriptures and Jesus as playing any role in God’s purpose. The destruction of Jerusalem did not convince them, but we will all see if that is true when the son of man in revealed.