Look at the government. The majority of the US government leadership is older white males.
Either you think: wow, white males are really good at getting into top government positions. Old white males must be superior to other humans.
Or you think: society really gives an advantage to older white males and it's much easier for them to get into government. Maybe power structures are balanced in their favour?
(Hint: the latter is true. The author of the article thinks along the lines of the former, that's why it's sexist and discriminatory and people are upset by it.)