Judging other people based on their appearance is never okay, no matter what people might say. It does not matter whether you would judge a person based on her skin tone, her appearance, her hair, the way that she dresses, and so much more. There are some people who look like they are kind, but the moment that you get to know them, you will realize that they are not as kind as they have looked.
Some people may look like they will do harm, but when you think about it, sometimes, those who do not look like they are the kindest will have the biggest hearts. The best thing that you can do is to make sure that you will get to know people first before making a decision.
No, I do not think that people should be judged by their appearances. Some people are actually very nice, but people may try their best to steer clear from these people because of the way that they dress. Someone who wears black all the time is not automatically someone who does not know how to smile. You should also not trust people based on how they look or how they dress.
This is one of the strategies that people use right now, especially when they want to steal from other people. They try to blend in with the crowd so that they will get what they want without being detected. There are so many things that people can do, so their appearance should not fool you.