Saying that one has nothing in common with a belief system is qualitatively different from saying that one has nothing in common with a particular group of humanity. Your commonality is your humanity, even aside from your baptism. I would hope that all parents would teach that to their children. Most Americans today have learned the opposite from Communist News Network and MSDNC: They have learned that people who voted for Trump are lower than human beings , "of a different breed," filled with "hate," are "racists," etc. -- merely for stating a voting preference, even. In marginalizing them, the Left has made it socially acceptable to hate people they do not know. It's not as if they merely state, in a condescending tone, that Trump voters were/are ignorant people to be respected nevertheless. There's no respect there at all because there's no recognition that someone who disagrees with one's own political belief system is an equal human being.
That illustrates the parallel danger in rejecting people rather than rejecting beliefs and behavior. I reject the behavior of 50+% of Mass-goers of the N.O. Their behavior at Mass scandalizes me and threatens my faith. So if there is no TLM available to me, I would no longer be interested in attending the N.O. But "those people" have been told the N.O. is "the true Mass," actually. They have been told that Mass is kind of an informal event (a "meal") -- which is why they behave the way they do at Mass; they are not behaving casually to annoy any traditionalists who happen to show up at that Mass. They have been catechized poorly and don't deserve to be segregated into a different segment of humanity because of their misfortune.
Can the same not be said about Protestants though? Or even many atheists for that matter. Some satanists too.
We shouldn't hate them, but we
should still label them as "non-Catholics". Not just their false religious beliefs, but
them as persons insofar as they subscribe to false religious beliefs.
They are not Catholic.
However, I'm still wondering about the ones who
don't subscribe to false religious beliefs. What about the Catholics who reject all the Vatican II errors while simultaneously believing that John XXIII, Paul VI, John Paul I, John Paul II, Benedict XVI, and Francis are popes? Is it really an act of "heresy" or "apostasy" to be of the opinion that Francis is pope, or to not be sure that Francis isn't the pope? When has the Church ever taught that Francis is
not the pope? (Perhaps those with faith are just supposed to somehow know that Francis is not pope? And if you don't know, it only demonstrates that you don't actually have faith?)