Frame your argument a little differently - you're saying you can't be proud / ashamed of anything your parents have done (that you didn't contribute to).
Pride or shame is by definition a feeling not legal culpability. A feeling.
Human brains seem wired to have strong feelings about their kin or tribe. So, yes, I would think having neutral feelings about your parents would be a hard thing to understand for most people.
You're technically correct and I agree with you, but you're missing the broader point: the goal of GP comment was to make the author of GGP comment feel better about having a high percentage of neanderthal DNA.