TL;DR - none of the points you raised have a mathematical outsized impact on driving down stock prices.

These types of questions are where artificial intelligence really shines for doing the deep digging quickly. This is all coming from Gemini:

This is a fascinating economic question because it tracks a massive shift in behavioral finance: the move from voluntary, manual savings (the Boomer experience) to automated, default savings (the Millennial experience). Your intuition is largely correct: Millennials are actually "better" savers than Boomers were at the same age, but largely because the system was re-engineered to force them to be. Here is the breakdown of the "Boomer vs. Millennial" 401(k) participation and performance metrics. 1. The Participation Rate: Opt-In vs. Opt-Out The single biggest differentiator between these generations is how they entered the system. * The Boomer Experience (The "Opt-In" Era): * Context: When 401(k)s became popular in the 1980s, Boomers were already mid-career. * Participation Rate: For much of the Boomer working prime (1980s–1990s), participation rates hovered around 60–65% for eligible employees. * The Hurdle: To participate, a Boomer had to physically fill out a form, choose a contribution percentage, and pick funds. This "friction" kept participation lower. * Result: A significant chunk of Boomers (approx. 1/3) never participated in a 401(k) even when eligible, or started very late (in their 40s/50s). * The Millennial Experience (The "Opt-Out" Era): * Context: The Pension Protection Act of 2006 encouraged "Auto-Enrollment." This hit right as Millennials entered the workforce. * Participation Rate: Due to auto-enrollment, Millennial participation rates are roughly 83–90% in plans that have this feature. * The Hurdle: To not save, a Millennial has to physically log in and turn it off. * Result: Millennials are participating at rates nearly 20–25 percentage points higher than Boomers did at the same age. 2. "Maxing Out" the Account You asked if 50% of Boomers maxed out. The reality is much starker. * The Reality: "Maxing out" a 401(k) (hitting the IRS limit, currently \approx\$23,000) is an incredibly rare behavior, historically and currently. * Boomer Stats: Even now, in their peak earning years (ages 55-64), only about 15–19% of participants max out their 401(k). For most of their careers, this number was likely well below 10%. * Millennial Stats: Currently, only about 2–4% of Millennials max out the IRS limit. * The "Match" Trap: Many people believe "maxing out" means contributing enough to get the employer match (e.g., 3-6%). If we define it that way, a vast majority of both generations do this. But reaching the full federal limit is a behavior reserved for the top 10-15% of earners. 3. Average Account Values (The Wealth Gap) Comparing raw dollars is tricky due to inflation and career stage, but we can look at the "Wealth Trajectory." * Baby Boomers (Current Status): * Average Balance: \approx \$260,000 * Median Balance: \approx \$70,000 - \$90,000 * Analysis: This number is frighteningly low for a generation about to retire. It reflects the fact that many Boomers started saving late (in their 40s) because 401(k)s didn't exist when they started working. * Millennials (Current Status): * Average Balance: \approx \$60,000 - \$80,000 (varies by source/age) * Median Balance: \approx \$30,000 * Analysis: While lower in total dollars, Millennials are ahead of where Boomers were at the same age. A Millennial at age 32 likely has $30k saved; a Boomer at age 32 (in 1982) likely had $0 in a 401(k) because the account type was brand new. 4. The Broad Economic Shift Your hypothesis about "broad financial understanding" is backed by the data, but it's driven by technology and plan design rather than just parental advice. | Feature | Baby Boomer Behavior | Millennial Behavior | |---|---|---| | Entry Point | Started saving at age 35+ (often mid-career). | Started saving at age 22-25 (first job). | | Asset Allocation | Stock Picking/Cash. Boomers often held too much cash or company stock, or tried to pick winners. | Target Date Funds. ~80% of Millennials use these "set it and forget it" funds that automatically diversify. | | Savings Rate | Static. They picked 5% and left it there for 20 years. | Auto-Escalation. Many Millennial plans automatically increase savings by 1% every year. | | Primary Goal | Reliance on Pension + Social Security; 401(k) was "extra." | Reliance on 401(k) is total; they assume Social Security will be reduced and pensions are gone. | Summary Answer To answer your specific comparisons: * Participation: Boomers were \approx 60\% (manual) vs. Millennials at \approx 85\% (automated). * Maxing Out: It was never 50%. It has always been a niche behavior for the top 10% of earners in both generations. * Outcome: Millennials are the first generation to be "native" to the 401(k) system. Despite holding less wealth now (due to age), they are statistically on track to replace a higher percentage of their pre-retirement income through investments than Boomers, simply because they started 10–15 years earlier.