I've managed older and younger high-achieving Millennials in tech and found that there are differences beyond the fact that one group is simply older than the other. Some generalizations and insights from my experience:
1) Attitudes towards "paying your dues" - Older Millennials were in the workforce during the 2008 recession and likely experienced a career pivot or lifestyle adjustment during that time, which taught them how to restructure their career paths and gain perspective on being employed. For most of their lives, they exclusively saw corporate executives as people who had spent their entire careers in one company or industry, starting from the bottom and working their way to the top. The young, billionaire founder/CEO persona did not exist in their minds until several years after they had already been in the workforce. As a result, older Millennials will see hardships, repetitive work, and new gray hairs as part of paying your dues as you work your way to the top.