it is possible to take these things to seriously. i didn't read the five love languages book end to end. it was enough for me to know that there are different ways to express love and that we have different preferences in what ways we notice love from others. that is the core that matters here, and is what helped me understand our relationship better.
same for MBTI. i don't know what specific MBTI type i am supposed to be, and i don't really care, but understanding the different aspects that MBTI is based on does help me understand myself better and let's me explain for example why i enjoy company some times and not at other times.
there used to be a time when astrology and astronomy where the same thing. astrology is pure nonsense, but the astronomy it is based on is not. in the same way MBTI may be nonsense, but the aspects it is based on probably are not.
to be a great listener it takes a few things, to listen, to give positive feedback and to help the other person work out what they want to say. listening itself makes up the biggest part. pretending to be a great listener may work in the short term, but someone will eventually figure out that you don't actually care about what they say.