Arguing with ignorant friends about religion.

You could introduce him to google?

He may have a point.

"At least some Baptists do not consider themselves "Protestants." This is to emphasize their sense that, insofar as the Protestant Reformation was as a contest between the Roman Catholic Church and reformers who sought to protest certain features of the Catholic Church and to reestablish the Church on what they considered was a purer basis, the Baptists have not entered into that contest. They have rejected the notion of a "universal Church" altogether, admitting the authority of only local organizations, individual communities of believers, and, ultimately, each individual before God. As a result, they have found themselves at odds with the Catholic Church, the Orthodox Church, and mainline denominational Protestantism."
teachinghistory.org/history-content/ask-a-historian/22329#:~:text=At%20least%20some%20Baptists%20do%20not%20consider%20themselves%20%22Protestants.%22,the%20Church%20on%20what%20they

I guess you could argue that, though how do you feel about people who are basically atheists but reject the term and insist on calling themselves "agnostic"? I believe that was actually Einstein's stance.

Don’t argue with him. It’s an identity thing, but I’ve never known Baptists...and I know a lot...who don’t think they are not also Protestants.  Anyway, there is no official Protestant Church, so who cares. 

Have him type, "are babtists protestants" into google. You can try to teach people but you can't make them learn. He sounds like a bit of a chore.


Edit: I just remembered that poll we had here a ways back asking how you indentify. I was the only person who selected Protestant, which is hilarious and almost certainly not the actual case. Funny though. Maybe people just don't want to be labled Protestant? Who knows.

Seems like all you would need to do is point him to do some research.

I didn't know they were the same thing either until this thread and then I Googled it and it seems you are at least mostly correct. 

From Google.

"At least some Baptists do not consider themselves "Protestants." This is to emphasize their sense that, insofar as the Protestant Reformation was as a contest between the Roman Catholic Church and reformers who sought to protest certain features of the Catholic Church and to reestablish the Church on what they considered was a purer basis, the Baptists have not entered into that contest. They have rejected the notion of a "universal Church" altogether, admitting the authority of only local organizations, individual communities of believers, and, ultimately, each individual before God. As a result, they have found themselves at odds with the Catholic Church, the Orthodox Church, and mainline denominational Protestantism."

There are ways to say things without coming off like an asshole and potentially ruining a friendship though. You could also just refrain from discussing religion if you think it will cause too many issues.