The reference to "one shall be taken and one left" is a reference to Zechariah's prediction that half of the people of Jerusalem would be taken away from Jerusalem as captives:
[Zec 14:1-2 KJV] 1 Behold, the day of the LORD cometh, and thy spoil shall be divided in the midst of thee. 2 For I will gather all nations against Jerusalem to battle; and the city shall be taken, and the houses rifled, and the women ravished; and half of the city shall go forth into captivity, and the residue of the people shall not be cut off from the city.
So what does it mean that "the residue of the people shall not be cut off from the city"? Perhaps it means that the ones taken will be disenfranchised, their goods confiscated and their rights terminated as a "felony". If so this might help explain the 1.1 million non-combatants killed in the judgment that fell around 70ad and why Revelation refers to the Jews hiding in the rocks of the hills, wishing that they had died in the war.
The birds come to pluck out their eyes as they eat their carcasses:
[Isa 5:25 NKJV] 25 Therefore the anger of the LORD is aroused against His people; He has stretched out His hand against them And stricken them, And the hills trembled. Their carcasses [were] as refuse in the midst of the streets. For all this His anger is not turned away, But His hand [is] stretched out still.
[Jer 9:22 NKJV] 22 Speak, "Thus says the LORD: 'Even the carcasses of men shall fall as refuse on the open field, Like cuttings after the harvester, And no one shall gather [them].' "
[Jer 16:18 NKJV] 18 "And first I will repay double for their iniquity and their sin, because they have defiled My land; they have filled My inheritance with the carcasses of their detestable and abominable idols."
It doesn't matter if it is a raven or an eagle!:
[Pro 30:17 KJV] 17 The eye [that] mocketh at [his] father, and despiseth to obey [his] mother, the ravens of the valley shall pick it out, and the young eagles shall eat it.
