Short answer: I don't know.You didn't answer my question. Why can't everyone perceive the "self evidence"?
Medium answer: I specifically avoided making any claim that reacting to General Revelation is universal.
Longer answer: I think a lot of atheists are not actually genuinely atheist to the core. A lot of them are reluctant to say matter and energy adequately explains life, the universe, and everything; reluctant to say love is nothing more than a chemical reaction between molecules; and few are willing to enthusiastically embrace moral relativism.
In other words, many of them are highly reticent to admit it, but they seem to have an innate sense that there is something more beyond matter and energy, and they can't help but to frequently appeal to a standard that is beyond human opinion or whim.