We Are Overcomers!

If Jesus has "overcome the world", as He said in John 16:33, then why do we continue to experience sin and tragedy like the school shooting in Uvalde, Texas? Has Jesus overcome the world or not? Or perhaps does "overcome" mean that He has shown the perfect way to "come through" or "come over" all the sin and pain that the world will throw at us? How do we cope with, and more importantly how do we respond to acts of evil? What does it mean for us to be overcomers?! How can we overcome evil with good, like Romans 12:21 says?