How do academics control their own biases?
Everything is in the end vetted by the community and by time.
Many researchers were fooled by their biases (including Galilei or Millikan who did systematic errors in their studies) and the biases were slowly uncovered by time. This is normal. Of course, a good researcher, as Feynman says, needs to take care not to fool themselves, and good researchers work hard to do so. In the end, however, it is time and the scientific community that filters out the wheat from the chaff.
One key thing to maximize your objectivity is to avoid p-hacking. Be aware what your hypothesis is before you run the experiment. Be aware of what parameters you extract from the experiment and how to factor them into your evaluation of the theoretical vs. experimental model.
Try to have at least two maximally independent ways of getting to a critical result. Understand the assumptions that got you a result.
Taking care of these various things will minimize the probability (it will never entirely go away) that you fool yourself and increase your confidence that you have done a proper job at doing good science.