I think it is.
Both the Novus Ordo and the traditional Catholic groups have an ecclesiology that ranks a number of men (even if the latter thinks that number is rather small) from all religions as being united to the Church.
Does anyone else recall listening to a sermon at: traditionalcatholicsermons.org/wordpress/
and having an example used of a illiterate Eastern "Orthodox" peasant in good faith / invincible ignorance?
I’d need to listen to that, but I wouldn’t bring up said ignorant peasant in an invincible ignorance context.
Rather I’d say he’s Catholic, barring a culpable decision of schism. Which, as an illiterate peasant, he probably hasn’t made