[Arkinsaw]

Shouldn’t the Atheist symbol be nothing? A lack of religion? Very odd to me that there is a religious symbol for Atheism.

[Wormwood]

Shouldn’t the Atheist symbol be nothing? A lack of religion? Very odd to me that there is a religious symbol for Atheism.

Mobilizing atheists is like herding cats, so a single symbol signifying lack of superstitious thinking seems unnecessary at best.

That said, here's an article that showcases some proposals.