Read Matthew 12:38-42
The Pharisees and scribes didn't believe Jesus was the Messiah/Christ though they saw his signs. However, the people of Nineveh repented and the Queen of Sheba was provoked to seek God by much smaller signs. What were they?
Others didn't believe when they heard Jesus' preaching and saw his miracles either. Read about them in Matthew 11:20-24.
The preaching of Jonah, the wisdom of Solomon, and the preaching and miracles of Jesus are all means of God's revelation of himself. God reveals himself in various ways. Read Hebrew 1:1-2.
What revelation of God is available in Nagoya? (For example, a Bible app on a smartphone.)
What revelation is available to all people everywhere? Read Romans 1:18-2:2 to read about the revelation to all people.
What must all people do to be saved? Read Romans 3:21-26, Acts 4:12, and John 14:6.