We humans are quick and mostly biased when asked about an opinion on most of the matters and it is not an individual's fault, our brains function like that. Our brains are also lazy like us. It doesn't want to look more deeply instead it quickly forms an opinion about people and other things with whatever info that is available without any effort.
Every now and then you will meet people and even without talking or knowing more about them, you will form an opinion by their looks, language etc. Just reflect on yourself and you will be amazed by how many times you do this. These opinions do slowly change after long interactions but how much time do we get to interact with new people nowadays!
I used to do the same and I consciously came to know about his partly by going through on a course on biases and partly by reading the book 'Thinking Fast and Slow'. I now try consciously to not form an opinion by the very limited data I have on the topic on which I am not well versed.
It's not only subjective topics in which our intuition is sometimes wrong. Let's dive into Mathematics for a second and try to answer this question. Please note the answer that comes to you fast and intuitively.
A cab was involved in a hit and run accident at night. Two cab companies, the Green and the Blue, operate in the city. 85% of the cabs in the city are Green and 15% are Blue. A witness identified the cab as Blue. The court tested the reliability of the witness under the same circumstances that existed on the night of the accident and concluded that the witness correctly identified each one of the two colours 80% of the time and failed 20% of the time. What is the probability that the cab involved in the accident was Blue rather than Green knowing that this witness identified it as Blue?
Did you came up with 80% ? You can see the answer here. Don't worry if you came up with wrong answer, most of us will come up with wrong one if asked to answer fast and intuitively.
Whatever I have written is also a formed opinion of my experiences and intuitions so you can outrightly reject it but before doing that, take a moment and think about it.