Yeeaah, she doesn't know what she's talking about.
I don't have a whole lot of experience with INFPs outside of my one friend who was uber cerebral and militant about his beliefs, though he was cool. I think he was somewhat unhealthy, though, which, according to the vid, means he was using his Te~!
Other than that, I had one friend who I'm pretty sure was an XNFP. She was really nice and sweet, but I knew if we ever got into a debate I'd be hitting my head against a brick wall. When moral issues are discussed, my go-to form of communicating my ideas is why and how they make sense objectively. She communicated her ideas according to the what was 'right' ethically. Usually, our opinions paralleled one another, since we're both pretty liberal, but we came from two completely different sources.
Tbh, though, I think the main reason why we couldn't discuss things wasn't because of ~Ti versus Fi~, but because she had, what seemed to me, an unexplored rationale for why she believed certain things for what she did. I had little problem talking with my other friend because he was smart, and had a pretty good rationale for why he believed things for what he did.