I hope the world doesn't ever become a majority of Atheists, or Fundamentalists of any religion. Both are incredibly bleak futures.
What exactly would make a world of majority atheists bleak?
The people who have problems with it have varying different reasons. I don't hate Christianity or Christians - heck, some of my favorite people are Christians - but I do think that Christianity and religion in general should be abandoned. My primary reason for thinking that is that belief informs actions. For example, if you believe that there are such things as witches and you also believe that your god has commanded that they must die then you're far more likely to go on a witch hunt. Though belief in witches has decreased in developed nations, this practice still goes on in others. Of course the typical response I expect when giving this example is "well that's not real Christianity", but considering that what constitutes "real Christianity" has been debated among Christians since Christianity came onto the scene almost two millenia ago I don't find that response particularly relevant.
But as I said, belief informs actions. If you believe something that is false and it causes you to act, the results of your actions are more likely to be harmful. Therefore I would prefer to believe as many true things as possible and as few false things as possible. The best means available for that is not religious faith, but rather empirical evidence.
A world of majority atheists would be bleak because Atheism, imo, is a very depressing and bleak worldview. Everything is an accident, we're all here for no reason at all. It makes life utterly worthless and meaningless. And also, it would be bleak because I don't think with Atheism will come rationality, they'll just be belief in something else, something worse. Also, since Atheism says there is no god, there is no foundation for morals in it. Nor ethics. Everything is nothing, right, so why be moral? I find as someone who was raised a Christian the whole moral relativism mindset which I've only seen Atheists espouse to be repugnant.
I'd take Agnosticism over Atheism any day. Atheists tend to be just as dogmatic and loud in their non-belief as Evangelical Christians are.
I don't believe religion in general should be abandoned. Yes, witch burnings still do happen in some areas and did. And they were wrong. When I was a Christian, I didn't ever think going around burning witches would be cool. I guess it's just the idea of sanity vs. insanity. One could stoop to blame the horrors of Communism on Atheism; I won't, but others have.
And since you said ''religion in general'' should be abandoned, what about all of the religions that have a much less bloody track record? Deism? Hinduism? Buddhism? Neo-Paganism (which is actually a rising set of beliefs)?
What of the good things religion does, and has done throughout history for the world? Are they to be overlooked for witch burnings and the like?
The idea that this universe, and you, and I, and everyone we love are all just accidents with no meaning or purpose is again, a bleak and depressing way of looking at things. And to proclaim with absolute certainty that there is NO God, is the same thing to me as a Fundie saying, "The Bible is 100% correct because it is 100% correct." There's no real proof on either side. You can rely on empirical evidence for whatever you believe in, but no one has ever proved with total, scientific certainty that God does, or does not exist. That is my main issue with Atheism, beyond it's mindset: It's just as arrogant as Fundamentalism is.
If we're going for a ''non-Christian or non (insert religion here) world", I'd like it if it was an Agnostic world. At least they don't pretend to know if God exists or not. It's probably the most humble path of them all.
