I believe that inequality is one of the most pressing issues of our time. On a national as well as on the global scale. However I'm not that sure if the inequality among generations is a big as the article pictures it. Most billioniares don't fall in the millenial generation. That disorts the picture. I assume that if those extrem rich wouldn't be taken into account the wealth gap between those generations wouldn't be that big.
Of course, salaries are crap and flattening for the last 30 years , rent is high, houses are expensive, and university degrees are huge debt, and on top of that, two economic crises in less than ten years apart. Meanwhile, you have an entire generation of baby boomers that want to retire like the great gatsby