As an HR Analyst too curious for my own good, I just found out that I'm the youngest person (28) in a large company to max out their 401k, and DW (33) came in at 38th (same company, different areas - I started after we got married).
Of the youngest 50 that maxed, the average salary is over 150k. DW and I made 60k and 70k respectively.
The only sad part is that we likely won't max this year since we just had a kid and DW reduced her hours (will make 40k in 2017, plus using daycare), but I'm still glad that we had one year of maxing everything we could this early on. There is a good chance that I could get a promotion this year, so we may get back to it sooner than we think.