I’m not going to replay an ontological debate that has been happening in the fields of sociology and psychology for decades with an engineer on the internet, who claims his own rationality a bit too hard. MBTI is considered pseudoscience because of its weakness against proper scientific validation processes, as well as its lack of support among both practitioners, theorists and researchers in the academic circles.
But to be clear, just because knowledge isn’t scientific doesn’t mean it doesn’t have value, there are tons of example like that that we use every day. The main issue I have with MBTI is that it takes the appearance of scientific knowledge, which I find deceitful and thus suspicious.