Interesting video. Sometimes we wonder the same thing, why does God allow bad things to happen to good people or simply bad things to happen. God is good why does he allow evil to exist? Dr. Alvin gave a good example of Job, the Book of Job, the prologue of Job, conversation between God and Satan:
"6 One day the angels[a] came to present themselves before the Lord, and Satan also came with them. 7 The Lord said to Satan, “Where have you come from?”
Satan answered the Lord, “From roaming throughout the earth, going back and forth on it.”
8 Then the Lord said to Satan, “Have you considered my servant Job? There is no one on earth like him; he is blameless and upright, a man who fears God and shuns evil.”
9 “Does Job fear God for nothing?” Satan replied. 10 “Have you not put a hedge around him and his household and everything he has? You have blessed the work of his hands, so that his flocks and herds are spread throughout the land. 11 But now stretch out your hand and strike everything he has, and he will surely curse you to your face.”
That could be a reason why evil exist but as Dr. Alvin mentioned, we don't know God's reason just as Job doesn't know reasons for his sufferings. YET he still remain faithful, trust in God, optimistic...h as the free will to think/reasons his life/experiences etc..
and so we too like Job has the same free will and how we respond will depend on our faith/trust in God like Job.
Also, if all we experience are just good things, beautiful things, will that make our life richer/more satisfying? Imagine if we live in a world where there's no sadness, no grief, no challenges and just pure bliss... Is that a better world or life as it is, a world where we taste the sweet, bitterness of life etc..
Maybe God wanted us to taste/experience/see all the flavors of life, the good, the bad, the ugly, etc..