system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do humans feel the need to identify so strongly with groups?

It would appear that when looking around you find people who associate all of their ego and being into one to two(or more) categories. Things such as Astrology, MBTI categories, Professional sports teams(that they root for, but are no a part of), Religion, etc. 
Using the example given, Ive seen people ask: My MBTI is XXXX  So what hobbies would be good for me?, We don't like 'sport team' fans here. , My Sign in 'x' what career should I have?

These seem to be very closed minded and ignore the more personal aspects that would be better off answering these questions. Is it due to misinformation or a tribal need to fit in somewhere?
gpt
We are social creatures by nature, so we have a natural impulse to find commonality with other people. Then, as we associate with a group, we adopt the qualities and beliefs of the group as part of our identity. 

Therefore, people defend and adhere to the ideals of the group because an attack on the group is perceived as an attack on the individual's identity itself. Even a carefully worded challenge to the idea itself will be perceived as an attack on the person, rather than an idea.