If miracles could have caused Sodom to repent, why didn’t God do them?

Answer:

"Then He began to denounce the cities in which most of His miracles were done, because they did not repent. 'Woe to you, Chorazin! Woe to you, Bethsaida! For if the miracles had occurred in Tyre and Sidon which occurred in you, they would have repented long ago in sackcloth and ashes. Nevertheless I say to you, it will be more tolerable for Tyre and Sidon in the day of judgment than for you. And you, Capernaum, will not be exalted to heaven, will you? You will descend to Hades; for if the miracles had occurred in Sodom which occurred in you, it would have remained to this day. Nevertheless I say to you that it will be more tolerable for the land of Sodom in the day of judgment, than for you'" (Matthew 11:20-24).

It is an interesting question but we can only speculate a bit because we lack too much information.

The miracles were those done by Jesus. But God had determined that there was a specific time for Jesus to arrive to make the greatest impact in the world. "But when the fullness of the time came, God sent forth His Son, born of a woman, born under the Law, so that He might redeem those who were under the Law, that we might receive the adoption as sons" (Galatians 4:4-5). "For while we were still helpless, at the right time Christ died for the ungodly" (Romans 5:6). Thus, if Jesus came early, perhaps he could have saved Tyre and Sidon or Sodom and Gomorrah, but it would not have changed the world as dramatically.

Chorazin, Bethsaida, and Capernaum actually had the Creator of the Universe walking, talking, and doing miracles among them! How sad that they rejected Him and how much worse it will be when they see Him again on Judgment Day.