I am a professional and the short answer is yes. No, not everyone is necessarily a racist, but yes, humans are hard-wired to create in-groups and out-groups, and to favor those in their group. What many people are able to do is to realize this pattern, and put effort into including the "outsiders" into their group. The problem is that leads to the creation of other, albeit different groups. So for example, even the most pro-love and pro-peace groups still "exclude" those that disagree and turn them into the "outside" group.
The truth is whether or not one realizes it, these biases exist naturally (if not based on religion/race/gender, then also a result of childhood experiences, etc), and the best thing a person can do is to be aware of these biases.
Now my opinion no longer science: If the right would stop saying "We're not racist" and the left would stop saying "yes you are" and instead, both sides said "you are racist, but that's okay, and let's become aware of implicit biases," we may actually get somewhere as a society.
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