I mean, this is not a good look from Facebook for the "oppressed conservative Christian minority" to be a false narrative.
I wouldn't cite this as an example of "oppression", but it's certainly a prominent egg on Facebook's collective face. With their resources, one would think they could make a model do better than label "Merry Christmas" as "discriminatory message". Unless they just don't care - and then conservative Christian minority has a valid basis for complaints.
Maybe the FB algorithm takes past posts into account? His account has probably been a fountain of misinformation and hate, and now he sends one innocuous message and is surprised it gets blocked. Yawn.
I think what you're looking for is called "social score" and the place you're looking for where they do things this way is China.