Your assertion that “No one forced him to” is faulty. True, it’s not like we held a gun to His head and demanded He create Hell, but our actions and choices do necessitate the existence of a place for those who chose against God in this life.
If He were to force an otherwise-damned soul to be in His presence eternally, that would violate that soul’s will, which was set against God. Since God will not violate our free will, He allows those souls who do not want to spend eternity with Him to be separated from Him. However, this separation also separates us from His goodness and His mercy, and so we cannot experience Good, and we must experience His justice.