Another explanation is that jobs have become harder to fill, and that's why companies are treating previously marginalized workers well. They know if they don't they'll have a hard time finding people to replace them.
Or it could just be that employers are now starting to realize the value of older, more mature, and more experienced workers.
Or maybe they're rejecting ageism as discriminatory, and want to treat everyone more fairly. Attitudes towards discrimination have certainly changed greatly over time, and a lot of discriminatory activity has become much less acceptable than it once was.
The explanations probably vary from company to company, from person to person, and from time to time. I'd be curious to interview hiring managers and older employees about this to get their take on it.
I see tons of ageism, across many industries.
Those same ageists will kowtow to anyone that can fit the role they're trying to fill.
Unemployment is measured in a length of time since their last position. Not the total amount of unworking people.
Probably not great to generalize "millennials".
They were able to get away with paying senior employees less for a how because that market was scared.