There do appear to be small differences between generations in work attitudes. Research has shown that older employees, on average, are slightly more satisfied at work, more committed and, therefore, less inclined to leave their jobs. There's little if any evidence, however, that younger employees are different because they are millennials. It's more likely that any differences stem from other factors, like career stage or societal changes—factors that everyone experiences.
Differences between millennials and other generations are likely overstated, and much of the evidence that purports to show differences is flawed. For example, many studies don't compare millennials to other generations and present findings as though they apply only to millennials. One desire typically attributed to millennials, for instance, is that they want more meaning at work. That could very well be true—and it could also be true that most people have started to look for more meaning in their work.
The fundamental feelings and thoughts that motivate people at work are, in all likelihood, not very different based on age. There're certainly different concerns in life that change through time; younger people can be more drawn to adventure and making money, while older people might be more concerned with family and legacy. But psychological research and theory support the idea that fundamental human needs, and the brain functions that support them, apply to everyone. Our research suggests that fundamental drivers of work engagement, such as meaning, autonomy and competence, don't differ much between millennials and older employees.