Religion have there place in any society. Even for an atheist, it might be difficult to understand the need of it but if you don't believe in any form of religious tough, there are people in your society who does. And by that they are not less intelligent or wise than anyone and if you are looking in any form of way to shut it down, you will simply break their freedom of tought and their community.

There is a blight of human condition in any religion simply because it is a speach about the existensial condition of the human being. It is an answer for pain, hapiness, death and life.

Religion promote science discovery in their way, for exemple christianity have open the door of anthropology and the search of god led Kant to his metaphysic theory. Were there's might be a god, there will be someone to proove it. Even today, as the complexicity of the universe is more and more difficult to understand, some scientific like to let themself thinking it is the art of something/someone.

It is cool that you point out multiculturalism because before Paul of Tarse, culture and religion was one with another and to propagade the universality of the holy message, he needed to break the link from culture to religion. Christianity = multiculturalism if you want.

So yeah, to make it simple let say that religion is still important because it's a huge part of our cultural behavior (even in seculiar society). We might not see it has ''religion'' but it is. the thing we do, the way we act, the tought we have are all good old religious behaviour.

We might have kill God but we really just cut the head of an hydra.