Those numbers are not age-adjusted:
Has the median man made progress economically since 1980? Not really. While male median income rose (in 2017 $) from $35,589 to $40,396, or 13.5 percent, this modest increase masks the fact that the share of men in their peak earnings years has increased, and that earnings at the median within peak earnings years categories have decreased.
Note that population share for 35-64, prime earnings years, rose from 1980 to 2017; earnings fell for every population group between 25 and 54. The median 30 year old is making less than their counterpart from 27 years earlier, as is the median 40 year old, as is the median 50 year old.
Had income within each age category remained constant at 1980 levels, current median income for men could be $40,306, or almost exactly where it us now.
Here is the full Richard Green post, with a useful chart, via Mark Thoma.