It depends on the dataset. The strongest correction is: it often does not peak at 35–44. In the current BLS full-time wage/salary data, the median is actually a little higher for 45–54 than for 35–44: $1,435/week vs. $1,384/week in Q1 2026, then it drops for 55–64 to $1,348/week. So the real pattern is usually not “35–44 is the clear peak,” but “earnings rise sharply through early career, flatten around 35–54, then decline after the mid-50s.”

The main reason is composition, not that every individual’s pay peaks at 40. Median earnings by age are a cross-section: it compares today’s 40-year-olds to today’s 55-year-olds. It is not tracking the same workers over time. The 55+ group contains more people who have left high-intensity jobs, moved to part-time/semi-retirement, become self-employed, shifted to lower-stress work, or been pushed out after job loss. BLS labor-force participation illustrates the selection issue: in May 2026, participation was around 84.9% for ages 35–44, 82.8% for ages 45–54, but only 37.1% for ages 55+.

Physical decline in blue-collar work is one piece, but it is too narrow. For physically demanding jobs, yes: injuries, chronic pain, stamina, and disability can move older workers out of full-time work or into lower-paying roles. That lowers observed median earnings among older age groups. But the pattern also shows up because of white-collar mechanisms: pay plateaus, age discrimination, fewer promotion slots, skills becoming obsolete, layoffs being harder to recover from, and older workers sometimes choosing stability/flexibility over compensation.

A useful way to think about it:

35–44: enough experience to be valuable; often at peak full-time labor-force attachment; still in “career accumulation” mode.

45–54: often equal or slightly higher earnings, depending on dataset; many are at senior individual-contributor, management, professional, or skilled-trade peak.

55–64: median starts falling because the group increasingly includes people reducing hours, exiting demanding jobs, taking lower-paid bridge jobs, becoming self-employed, or being involuntarily displaced.

65+: much more heavily selected toward people working by choice, necessity, or in lower-hour roles; not comparable to prime-age full-time workers.

Also, wealth usually peaks much later than earnings. A 55-year-old may have more net worth than a 40-year-old because of home equity, retirement accounts, and compounding, even if annual labor earnings have flattened or fallen. So the apparent paradox is partly from mixing up income flow with asset stock.

So: your hypothesis is directionally valid for some manual workers, but the broader answer is labor-force selection + career plateauing + exit from high-intensity work + age discrimination/job displacement + voluntary downshifting. It is not mainly that workers over 50 are categorically “beaten down”; it is that the median over-50 worker pool is no longer the same kind of full-throttle, full-time, advancement-oriented pool as the 35–54 group.

(http://www.autoadmit.com/thread.php?thread_id=5878029&forum_id=2betting#49967230)

the most obvious explanation is usually the correct one

(http://www.autoadmit.com/thread.php?thread_id=5878029&forum_id=2betting#49967270)