Is this some sort of remnant of evangelical puritan protestant ideology?
I don't understaun this.
If you ask me, it'd make as much sense as Orthodox and Christians.... or Shia and Muslim...
I know not all Christians are Catholics but for feck's sake...
They're all Christians to me....
Edit:
It's a U.S thing but this is the sort of things I hear...
https://www.gotquestions.org/Catholic-Christian.html
I am a Catholic. Why should I consider becoming a Christian?
I now know more distinctions (apparently Catholicism requires duty and salvation is process, unlike Protestantism?) but I still think they're of a similar branch (Christianity) so I just wonder the social factor
As an American who was raised Lutheran, who was taught a bunch of Romance-Euro-centric world history in school, I always considered Roman Catholic to be the "default" flavor of Christianity. Protestantism in all of its forms are hard forks. It's in the name, even--the Roman Catholic church is what Protestants are "protesting".
To unironically "-and Zoidberg" Catholicism out of Christianity while leaving Protestant flavors included feels completely backwards. I've never heard anyone do it.
But if I did, I could only assume it was due to some No True Scotsman bullshit. "Only we practice the correct way. Everyone else isn't just interpreting it differently, but interpreting it wrong." Sounds like an Evangelical line of thought to me.