Estate law in the U.S. allows people to leave their wealth to whomever they want with very few restrictions. In some other countries, people have very few choices on the inheritance of wealth.
When people go to an estate planning attorney in the U.S., they will learn that there are very few legal restrictions regarding the distribution of their wealth after they pass away.
People are required to make sure their spouses and minor children are taken care of, so they cannot simply be disinherited. However, if people want to, they can disinherit their adult children, their grandchildren or anyone who is not their spouse or minor child.
This is because estate law in the U.S. has been developed to give as much freedom to people as possible in deciding who should receive an inheritance from them.
Some other countries do not all give people a similar amount of freedom as the Wills, Trusts & Estates Prof Blog discusses in "Disinheritance vs. Forced Heirship."
Estate laws in France have been developed to protect heirs from disinheritance. The children of the deceased are entitled to a certain share of their parent's estate.
This is common in Europe.
Some people believe that this forced heirship leads to greater inequality and dynasties, since it does not allow people to leave a large share of their estates to charity.
Since most people in the U.S. choose to leave their wealth to their children without being required to do so, it is not clear how much of an impact the difference makes.
Reference: Wills, Trusts & Estates Prof Blog (Jan. 14, 2018) "Disinheritance vs. Forced Heirship."