I have also spoken to a number of developers older than me who are far behind. Like they didn't understand the point of Ruby or Node and thought Php was just fine. Or they thought that all of the organizations code should go in two giant repos like the old svn way.
So the reality is that sometimes older people aren't up to date or don't share your culture.
Having said all of that I personally believe that in most respects younger developers are just as far behind as the older developers and often lacking quite a bit if perspective. Whereas older developers need to update their perspective.
Obviously it depends on the person so generalizations like those are usually going to be counterproductive because the best developers are in their own category