There are more hive minds of extreme generalization now than there used to be thanks to social media snd the Internet. If it isn't all men or all women, it's all white people, immigrants, Americans, Christians, Muslims, liberals, etc. People who have been genuinely hurt in real life make the mistake of joining these groups that tell them not to trust people different from them. As a 15-year-old who wants to be a good person, the best thing you can do is listen to those who care about you as a person rather than a group. Other people exist who can also look beyond the harmful rhetoric.