We take obviously mostly-genetically-determined traits like height, eye/hair/skin colour, facial features etc, then extrapolate to argue/assume that all kinds of other things must also be genetically determined, like cognition, behavioral patterns, emotional patterns, for which there is far less evidence of them being hard-coded in DNA. This will be confounded by the fact that we can often see commonalities in these factors from parents to children and between siblings, and assume these commonalities exist due to genetic coding, not recognizing that there are other forms of inheritance/conditioning that can explain these commonalities, but that even if these inherited patterns are deeply ingrained, they can be altered via the right practices (emotional “letting go” being the most important in my experience).