"This is the generation of the great LEVIATHAN, or rather, to speak more reverently of that mortal god, to which we own under the immortal God, our peace and defense." -Thomas Hobbes: Leviathan
Never waste time engaging an atheist who spends more time trying to convince you that atheism is good for you/the world rather than that atheism is true, whatever the consequences.
What he is doing is propagating a sales pitch, not advancing a proposition. He is already personally invested in his ideology of the alleged benefits of atheism rather than concerned with objectively determining whether atheism is true or false, regardless of its effects upon our hopes and desires. As long as he derives some psychological comfort or hope from his atheism, there is no hope of using factual arguments to convince one and one should engage only for the benefit of others who might be so swayed by his arguments.
Sometimes you argue to convince, sometimes you argue to prevent them from convincing others.