Individualism vs Communitarianism is a very well studied broad example (with a nice bimodal distribution) and leads to pretty strong disagreements about some fundamental values for people from different cultures.

Worldview and religious differences also lead to disagreements about fundamental values. And among other concrete examples that I personally think are important: how much respect should be given to religious/spiritual/supernatural beliefs, what rights are inalienable human rights, how people with various illnesses should be treated, how resources are distributed, what behaviour is acceptable during disagreements (on large scales and small) and what subjects/ideas/beliefs/actions are taboo seem like the big ones.

Some cultures have hard time admitting, for example, that societal and legal rights for women and men should be as matched as possible.

Some other cultures got there mostly.

When these cultures meet and interact, the former just become stronger in their misgivings.

Language and religion are big ones.

I took the comment to mean that the complaints of many racists are really often more about what they perceive as "culture" rather than actual genetics. They simply use skin color as a signal and a proxy in assignment because racism is essentially a form of mental laziness.

The Inuit people, among similar cultures, are having a problem with diabetes because their bodies adapted to a hunter's diet of high protein and fat low in glucose prior to the introduction of agricultural products from colonialism. Darn, that's actually a biological difference too.

https://www.txbiomed.org/news-press/news-releases/inuit-diab...