Life Under Secularism

Pick any nation that is not secular or industrialized and compare it to one that is.

http://hdr.undp.org/en/countries

While you may find exceptions, practically speaking every nation that falls under the categories of both “secular” and “industrialized” will rank higher in terms of human progress. That means not just gross GDP but civil rights, quality of life, opportunities and so forth. Human progress means individuals are free to pursue whatever they feel makes them happy in such a way that they’re not in constant strife with their neighbors. While religion may have been a prominent part of their past it no longer has the power to compel people in these nations to be religious or to behave according to religious values. Religion is a choice, not an obligation. The most respected people in these societies are not those who wear their religion on their sleeve but people who contribute the most to their societies without needing to broadcast their religious affiliation. Religion has a largely ceremonial function in these societies and as a consequence a growing percentage of those societies identify with no religion.

People in these nations aren’t desperate. They’re not worried about where their next meal is going to come from or how they’re going to pay the bills coming due. They’re generally not worried about getting sick and losing everything because they can’t work or having to toil in a menial job until they die because there’s no way to pay the cost of living otherwise. What we’ve learned is that there’s a demonstrated correlation between inequality and religion.

https://www.russellsage.org/awarded-project/relationship-between-inequality-and-religion

The more inequality people perceive in their societies the more religious they tend to be. High inequality makes it hard for people to ignore their own plight. They can’t help but face the fact that they don’t have security in their daily lives, that a bad accident or an unexpected bill can tip them over the edge of hanging on into destitution. So they turn to anything that offers hope, even if it’s a lie. Religion feeds on fear and insecurity.

If you wish to nitpick the HDI rankings then look at others.

https://www.usnews.com/news/best-countries/quality-of-life-rankings

https://www.numbeo.com/quality-of-life/rankings_by_country.jsp

https://worldinfigures.com/rankings

You may find exceptions where highly religious societies rank higher in specific indexes, but by and large the vast majority of places where it’s good to be alive are secular. That doesn’t mean religion is forbidden in these places, it means religion doesn’t dominate people’s lives. If civil rights is even remotely a concern for you then secularism is the way.

We also have contemporary research showing that religious indoctrination doesn’t promote progress:

This paper studies when religion can hamper diffusion of knowledge and economic development, and through which mechanism. I examine Catholicism in France during the Second Industrial Revolution (1870–1914). In this period, technology became skill-intensive, leading to the introduction of technical education in primary schools. I find that more religious locations had lower economic development after 1870. Schooling appears to be the key mechanism: more religious areas saw a slower adoption of the technical curriculum and a push for religious education. In turn, religious education was negatively associated with industrial development 10 to 15 years later, when schoolchildren entered the labor market.

So why does the world work this way? In part, it's because modern governments are held accountable by the people they govern. When they're not then abuses and atrocities escalate. But it's also because people have the ability to compare promises made against promises kept. When governments make promises that they don't keep, those governments ultimately fall. But religions make promises [that can't be checked, let alone kept which is what makes them uniquely harmful in ways that governments aren't.

Here is independently verifiable evidence that human progress happens in spite of religion, not because of it. The goal is not to turn the world atheist; that's a choice everyone should be free to make for themselves. The goal is to turn the world secular, so no one is coerced into a choice they don't agree with. The end result is that the demand for religion diminishes with each generation as people discover they simply don't need it.