More than meaningless I think MBTI is dangerous. It creates a false dichotomy between introvert and extrovert and then assigns you to one camp or the other. People then, especially those assigned introvert, limit themselves.

Introversion is not a diagnosis. You can be extroverted during meetings and introverted at your desk. If you 'lean introvert', it means you could work on exercising your extrovert muscle. It goes the same for the other way. Learning how to be introverted at the right time is a benefit to all extroverts.

The danger with MBTI is in making you think these are medical diagnoses and you're trapped being one thing or the other. I've worked with people who think they are extroverts and read books like "How To Work With Introverts." These people are dangerous. So are employers that want to know your type. They will limit your career growth depending on their prejudices. This is no different than you career suffering because you aren't a Pisces.