The argument you appear to being attempting to support is:

> Global inequality is actually decreasing (potentially at the expense of Americans).

The link you have [1] states that "While the steep rise of inequality in the United States is well-known, long-run data on the incomes of the richest shows countries have followed a variety of trajectories."

Also, "high and rising inequality is not an inevitability; it’s something that individual countries can influence".

This does not say anything about a global trend. This support nothing except that counties can influence inequality levels.

[1]: https://ourworldindata.org/how-has-income-inequality-within-...