Can anyone compare and contrast between the two and which of them causes more damage to the society?

The developmental stages of life are based on learning and relearning of ideas, values and knowledge about society. When a person fails to understand other perspectives other than one’s own it is called egocentrism. The existence of egocentrism in society is the existence of egocentric perspectives. For example, a child touches a hot metal pot because her mother often uses it shows that the cognitive skills of the child are not well-developed and the child has failed to understand the consequences of his action. Egocentrism is most common in children as compared to adults because adult people are faster to learn and to correct their egocentric perspective. In closed societies, egocentrism exists almost in the whole society.
Egocentrism, on the other hand, is the feeling of superiority of one’s own culture. People feel the superiority due to its different components of culture like language, religion, ideology, arts and nomenclature etc. Ethnocentrism, as sociologist William Graham Sumner (1906) described the term, involves a belief or attitudes that one’s own culture is better than all others. Almost everyone is a little bit ethnocentric.
For instance, during Europe’s colonial expansion, European colonizers often viewed the people they colonizied as uncultured savages who needed European governance, dress, religion and other cultural practices. In reality, the colonizers were guilty of cultural imperialism.
Difference: Egocentrism mostly exists in individuals while ethnocentrism exists in the whole society.
Egocentrism means an individual or group of individuals have failed to learn other’s perspectives. While Ethnocentrism means a high appreciation of one’s own culture and disdain or dislike for other cultures. Egocentrism is easy to change as compared to ethnocentrism. Sometimes, Ethnocentrism is considered healthy and necessary as compared to egocentrism for society.
Similarity: both exist in society. Both affect the behaviour, attitude and lifestyle of individuals. Both define individual as well as social patterns and phenomena in society. Both are responsible for the diversity of human societies around the world…..
Damage to the society can be assessed based on the intensity in a society.

Ethnocentrism is the tendency to look at the world primarily from the perspective of one's own culture. Egocentrism is defined by having or regarding the self or the individual as the center of all things.