I have been a diehard atheist since my teenage years. It's always been obvious that religion is a result of primitive minds trying to explain the unknown. God(s) were once credited for making the sun rise and ensuring a good harvest. God(s) wrath was once blamed for famines, earthquakes and other natural disasters. Science has been consistently proving religion wrong for centuries.
Religion has been responsible for wars and countless other atrocities since the beginning of humanity.
Religion does no harm... Does it? (archive.org)
Even today religious groups hold back scientific progress such as stem cell research that could potentially save millions of lives via new cures.
Religion is almost universal across the human species so it exists for good reason. It encourages a sense of unity amongst its followers. Which in turn increases odds of survival and reproduction. Even if the beliefs themselves are irrational nonsense. Christianity encouraged monogamous marriage and with it the building of western civilization.
Ultimately religious "hardliners" have more children than "moderates" who in turn have more children than the non religious.
As much as I hate to say, it will be the religious who will inherit the world in the future.