The human brain has all kind of biases, but the human brain, while terrible at processing logic or remembering facts, is extremely good at recognizing patterns. Which is why we are still so much better than even the most powerful computers at recognizing things. It's also why oncology still works with human doctors (even though they are spending billions to develop cancerous cell recognition software, but 99% of the work is still made by pathologists that look at cells with their microscopes ). It's also why computers suck so much at reading emotions. The human brain, but actually the mammal brain in general, is ultra specialized at pattern recognition, it's a huge evolutionary advantage.
Part of what makes us so good at pattern recognition is that our brains will tend to fill up missing data (which is can draw a stylized cat with a couple of lines and you will still recognize it's a cat.) This is a feature, not a bug. Of course it means that if we are unaware of our biases we might have a tendency to make up stuff, but people who are used to work with data learn to avoid those biases.
Now, models based on historical data are a whole other story. It's actually trivial to make models that outperforms passed decisions, it doesn't mean it's useful at all to predict the future.
