IMHO:
The Whore of Babylon is not itself Babylon.
“Babylon” itself (Rome) destroys its “Whore” (Jerusalem).
Revelation 17:16: And the ten horns which thou sawest in the beast [Rome]: these shall hate the harlot [Jerusalem], and shall make her desolate and naked, and shall eat her flesh, and shall burn her with fire.
Revelation 11:8 : [A]nd their dead bodies will lie in the street of the great city which is allegorically called Sodom and Egypt, where their Lord was crucified.
Revelation 13:18: This calls for wisdom: let the one who has understanding calculate the number of the beast, for it is the number of a man, and his number is 666 [Nero].
Isaiah 1:21: How the faithful city has become a harlot, she that was full of justice! Righteousness lodged in her, but now murderers.
Jeremiah 3:6: The LORD said to me in the days of King Josiah: "Have you seen what she did, that faithless one, Israel, how she went up on every high hill and under every green tree, and there played the harlot?”
Ezekiel 16:2: Son of man, make known to Jerusalem her abominations.
Ezekiel 16:26-30: You also played the harlot with the Egyptians, your lustful neighbors, multiplying your harlotry, to provoke me to anger. Behold, therefore, I stretched out my hand against you, and diminished your allotted portion, and delivered you to the greed of your enemies, the daughters of the Philistines, who were ashamed of your lewd behavior. You played the harlot also with the Assyrians, because you were insatiable; yea, you played the harlot with them, and still you were not satisfied. You multiplied your harlotry also with the trading land of Chaldea; and even with this you were not satisfied. "How lovesick is your heart, says the Lord GOD, seeing you did all these things, the deeds of a brazen harlot.
Matthew 23:29-38: Woe to you, scribes and Pharisees, hypocrites! for you build the tombs of the prophets and adorn the monuments of the righteous, saying, ‘If we had lived in the days of our fathers, we would not have taken part with them in shedding the blood of the prophets.’ Thus you witness against yourselves, that you are sons of those who murdered the prophets. Fill up, then, the measure of your fathers. You serpents, you brood of vipers, how are you to escape being sentenced to hell? Therefore I send you prophets and wise men and scribes, some of whom you will kill and crucify, and some you will scourge in your synagogues and persecute from town to town, that upon you may come all the righteous blood shed on earth, from the blood of innocent Abel to the blood of Zechariah the son of Barachiah, whom you murdered between the sanctuary and the altar. Truly, I say to you, all this will come upon this generation. ‘O Jerusalem, Jerusalem, killing the prophets and stoning those who are sent to you! How often would I have gathered your children together as a hen gathers her brood under her wings, and you would not! Behold, your house is forsaken and desolate’.
Revelation 18:20, 24: Rejoice over her, O heaven, O saints and apostles and prophets, for God has given judgment for you against her! And in her was found the blood of prophets and of saints, and of all who have been slain on earth.