You've got it the wrong way round. Atheism is the default setting. Unless someone exposes you to religion, you simply remain an atheist. Hence, atheism cannot leave you.
And from personal experience I can tell you that a shaking plane did not make me a believer. It just made me kiss my wife and crack stupid jokes like how we don't have to worry about bombs on the plane or hijackers anymore.
Overall, religious affiliation is in decline in vast parts of Europe. Therefore, children growing up around here have a good chance of coming into contact with organized religion pretty late in their development. That is what I meant. I will concede the point that not coming into contact with any religion is almost impossible. But the later in life this contact happens the more unlikely it is to become a theist.
And from personal experience I can tell you that a shaking plane did not make me a believer. It just made me kiss my wife and crack stupid jokes like how we don't have to worry about bombs on the plane or hijackers anymore.