Doesn't have to target practicing or devout christians to be effective Christian propaganda. Most people in NA are culturally christian and nearly half believe in ghosts. I watched them recently in search of some junk-food horror and out of curiosity of its success. The first one is a blatant villification of women who get abortions and the second one is about apostasy. They specify that the spirits of people who are the cause of this harm are ones that commit sins, they're evil because they aren't christian. In both films, the solution was for the Warrens to deepen their faith or flex it to overpower the demons not through action or change but pure faith. These narratives very strongly reflect a Christian upbringing where authority must be respected at all costs and faith in inaction is more valuable than active change that may bring criticism to systems of power.

This is of course ignoring that Ed Warren was a grooming pedo pos. He and Lorraine were scammers that hated each other and are on record multiple times purposefully manipulating christian iconography and values to the benefit of their stories. The fact they're portrayed as so devout is to lend credence to their roles as heroes in these stories.