Mindfulness is necessary. Religion provides us with mindfulness in the personal, interpersonal, social, and political realms by the use of ritual, feast, festival, and myth. There are biological and circumstantial reasons why we need mindfulness in a world no longer consisting of hunter gatherer bands.
The problem, religion is the ABSOLUTE WORST POSSIBLE way of achieving mindfulness. And of the worst possible kinds, Abrahamic Monotheism is the ABSOLUTE WORST POSSIBLE religion.