I think it is an argument due to the speaker criticizing God's goodness and power. They're directly saying that God is lacking goodness, power, or even both. The speaker probably doesn't believe in God due to their strong belief that God isn't all that powerful nor good as much as people claim him to be; moreover, the speaker says that God should've made all his creates happy, which shows us that the speaker isn't all that happy themselves hence them expressing their thoughts within that quote.