Yeah, cause while blood type is like horoscopes which absolutely no meaningful information, silly personality quizzes at least tell you back what you told them, so some kind of correlation exists, even if the categorization and implications are basically spurious.
I'm not sure they're really "into" mbti. Most of the people I know who know about mbti talk about their result ironically. About as seriously as talking about their star sign or which planet is in retrograde. I've yet to see anyone actually into it.
I believe that's more of a thing in east asia. I've stumbled upon it only a few times in English speaking media and never here in Sweden. Though people were obsessed with some colour thing a few years back
