Not actually true. a more accurate telling is: the rich get richer and the poor get richer too. You may commenting on the fact that the rich are getting richer FASTER than the poor are getting richer, and that's an interesting phenomenon to comment on, but it is undeniable that everyone is getting richer, almost regardless how you slice the data.
Worldwide, extreme poverty is on an accelerating decrease, and is set to be completely eradicated by 2030. In the US and in Western economies, poverty, which used to be common only 80 years ago, is almost completely erased. Meanwhile those who have low income, but are above "the poverty line", continue to see growth in wages, in standard of living, and in lifespan and in quality of life. Objectively.
Why are we are inundated with the false idea that "things are so bad" by mainstream media? That narrative sells papers and clicks. But it's not supported by the data.
Whether we all would benefit from rebalancing the wealth distribution is a different question.
reference: Humanprogress.org, and Steven Pinker's new book, "Enlightenment Now" (highly recommended)