The article simultaneously points out that white millenials are no less tolerant than their parents while also observing that they're a vanishing breed. Imagine this sentence written in 1945:

The fact of the matter is that millennials who are white — that is, members of the group that has always had the most regressive racial beliefs, and who will constitute a majority of U.S. voters for at least another couple of decades — are, on key questions involving race, no more open-minded than their parents.

Think about that for a minute - the author is casually dismissing the fact that sometime in the next 30 years, white people will no longer be a majority. That, right there, is the majority of the bugshittery over on Fox News - the fact that your grandkids are going to be outnumbered by "those people." Yet this article pretty much sweeps it under the rug to nit-pick study methodology.

Know what's great for tolerance? Necessity. If every Starbuck's is full of interracial and same-sex couples, you've got two choices: get used to interracial and same-sex couples or stop going to Starbuck's. And when you substitute "everywhere" for "Starbuck's" you either chill out or move to Sandpoint.