I'm not sure what "modern" means. I'm not sure anyone knows what it means, because the term is so broad that it gets used in a lot of different ways. But that is not to say that the term is meaningless. There are some consistencies in the way the word is used. One of those consistencies has to do with secularity: modernity entails a viewpoint that understands basic questions about the universe from a secular perspective. What causes the events in a person's life? What is the origin of the universe? Where do human beings come from? If your understanding of these issues does not assign primary significance to divine beings or forces, then in this respect you have a modern world view. This does not mean that people with a modern world view don't believe in God, but it does mean that they accommodate that belief to what they understand to be scientific and secular explanations.

Lots of people, even in the contemporary West, do not have a modern world view. In most of the world, this is not because they have not heard about modernity, it is rather because they know about it and they reject it. I am probably not the person to explain their objections, since I do not share them, but it is not difficult to see that indeed one could argue there are some downsides to secular modernity (For example: the collapse of communal values, a pervasive sense of anxiety and meaninglessness, loosening of restraints on consumption and sexual behavior, and so on).