I never insulted you, I merely made an assertion from a well gathered assumption.
I'm going to make this as short as possible, as I hate cycling through repeated facts. To understand this, one must understand a sliver of how genetics work. However, even that though simplistic isn't required, a simple example should suffice.
Q: My mother, and father have brown eyes -- I have green. Why do I not have brown eyes?
A: Recessive genes.
Q: Why had Onoki's kin not inherited the capability to use Jinton?
A: Insufficient chakra natures i.e. Sasuke & Itachi were of the same blood, yet one possessed lightning, and the other water.
A2: Onoki's genes allowing him to be compatible with Mu's Kekkei Tota Jinton were recessive genes, while the dominant genes were passed on to his kin granting them the inability to perform Dust Release.
Simplistic.