This and Bates Motel are prime examples of protagonists that DON'T work
I haven't seen Damien so maybe I'm far off but I feel like they are taking the same approach as Bates Motel in that their main character is someone trying to be good but just can't help the evil that's inside of them.
This is not a protagonist that people can get attached to: it gets so old watching them jump from good to bad to good, asking themselves "what's wrong with me?".
It reminds me of the show Point Pleasant which had a very short run - the main character victimizes themselves for having uncontrollable evil inside of them but still try to be portrayed as goodhearted and sympathetic..I just don't buy it and can't get invested in it.