It often appears to be laughter at the human, from a divine perspective. Croilus laughs from the eight sphere. Critics often hear a sardonic, cynical tone to his laughter. They are twentieth century critics. Mozart himself is able to hear in his music.
Divine laughter is helpless laughter.
And of course it is healthy. Not only purgative, but a humbling realignment with the force for life that laughs at the meager attempts of human authority to impose its own order on things.