In astrophysicists chronicles of pluto what reason does dr tyson give for excluding pluto from the museum exhibit?

Dr Tyson excluded Pluto from the American Museum of National History exhibit because it is considered an icy body and not a planet.

Originally, he identified Pluto as a comet from the Kuiper Belt of Comets, since its composition its mostly ice, and stated that if it came near the sun it would evaporate and grow a tail, an uncommon behavior for a planet.

Eventually, in the 1990s, icy bodies were found in the outer solar system, and the similarity between Pluto and them was evident. The conclusion was that both are made of ice, have similar strange orbits, and cross the orbit of other planets.

the african society basically suffered the consequences of colonization and apartheid directly attacking the black people, first, during the colonialism and its main idea which which "white people" had better rights, affecting   them principally in the right to establish black people in their territories, access to quality education and health services and took away any civil right even to the black people to feel they have the same opportunities as the settlers.