Good question. Each generation's brains are essentially the same from a neuro-biological point of view. But the great mystery is why different brains react differently in the same situations? The amygdala sits within the limbic system in the brain. Memories and experiences are stored there. Can we say this is also the place that stores our values, our belief systems - possibly, but no-one knows for certain and there are heaps of theories. But these are what impact the various generations' reactions to the world.
The neuro-scientists can tell us that the neo-cortex in young people (teenagers) is still coming to full form whereas their amygdala is already functioning from a very early age. Maybe that's why they go off at things we don't think are that important - they don't have the ability to moderate their behaviour as well as adults.
And at the other extreme, baby boomers and seniors, have probably 'seen it all' and have taught themselves, either deliberately or by accident, to allow the thinking brain more time to click in when something stirs them up.
Underpinning our reactions are the neuro-patterns we have stored and that our amygdala identifies as a threat to life as we know it. Our experiences individually and in groups, at school, our social and work environments, the influence of the media, religion, world events and so on will all impact on what our amygdala perceives as life threatening. So yes I think there is a difference between generations, just as there are differences between individuals. It is a multi-layered response.