I have been taught to stand arm in arm next to all who proclaim Jesus Christ as the Son of God, accept the Trinity, the Apostle and Nicene Creed as a brother or sister in Christ. This despite any differences we have regardless of how significant.
Personally, I believe that no one should turn away from Truth as has been revealed to them, to which we are to offer such truth to others as God commands, yet, without judgment of those that seek God in a different way from our own.
I have heard many great jokes, the most recent one on this site, and am aware of the differences between Catholic and ‘Protestants’. I have never heard anyone (to me personally) accuse them of not being Christian. I am well aware of the hateful things that are said and done amongst many though, and well, hate and judgment is not exactly what we all strive for is it.
Peace & Grace I say - I’m confident our Lord God will be fair in judging us all.