This describes something that could have happened in the past but did not. Yahweh actually did leave a small remnant. (See: [[rc://en/ta/man/jit/figs-hypo]])
How Judah would have been like Sodom and Gomorrah can be made explicit. Alternate translation: "God would have destroyed us, like he destroyed the cities of Sodom and Gomorrah" (See: [[rc://en/ta/man/jit/figs-explicit]] and [[rc://en/ta/man/jit/figs-simile]])