Christian commentators generally understand this language as describing God's genuine sorrow over human sin in terms that people can comprehend. Scripture frequently uses familiar human expressions to communicate something about God's character and His relationship with humanity.
Some theologians emphasize that God's knowledge and eternal purposes do not change. His regret therefore does not mean that He discovered an unexpected mistake. Rather, it expresses His holy opposition to the wickedness that had overtaken His creation.
Other Christian interpreters place greater emphasis on the reality of God's grief. The language is not merely decorative. It reveals that human evil is deeply offensive to the God who created humanity for goodness and fellowship.
These understandings need not be opposed. God can know what human beings will do while genuinely expressing sorrow over their wrongdoing.