Why does the existence of evil necessarily mean God does or may not exist?

This is an interesting question I saw on quora.

The existence of evil is fatal to a specific type of god, the all loving, all knowing all powerful kind. But for those who believe in a god that suffers with us, or a god that is not all loving nor powerful nor knowing is not affected by the presence of any amount of evil.

There are theodicies that try to explain the compatibility of God and evil as we experience in the universe.

There are for example the argument that this is the best of all possible worlds, or that freewill can explain the evil( though this doesn’t explain natural evil), or that this is a place for preparation or learning or that we don’t have the understanding necessary to know why evil exists.