I don't know that the data I'm seeing above supports that... But I figured I'd look every 5 years so I'd be able to sort the Boomers out from the Silent Generation and GenX.
So, the number of Boomer Private Pilots was:
2000 (Boomers aged 35-55): 90,208 ATP, 49,754 Commercial, 132,102 Private, 35,110 Student, 317,742 total (Rotorcraft Only and Glider Only are excluded in this data)
2005 (Boomers aged 40-60): 90,166 ATP, 52,950 Commercial, 126,802 Private, 27,368 Student, 297,511 total (All aircraft)
2010 (Boomers aged 45-65): 83,314 ATP, 46,069 Commercial, 102,378 Private, 14,725 Student, 2,405 Sport, 248,987 total (Airline pilot age limit went from 60 to 65 on December 13, 2007 but some ATPs still would have aged out.)
2015 (Boomers aged 50-70): 77,050 ATP, 40,327 Commercial, 85,389 Private, 11,872 Student, 3,292 Sport, 217,996 total
2020 (Boomers aged 55-75): 65,845 ATP, 32,017 Commercial, 63,684 Private, 21,176 Student, 3,773 Sport, 186,554 total
2024 (Boomers aged 59-79): 47,608 ATP, 27,179 Commercial, 51,449 Private, 24,965 Student, 3,972 Sport, 155,209 total (I used the 60-80 age groups here.)
ATPs decreasing isn't too big of a surprise - Not many people get their ATP when they're older, and of course those aging out and not picking back up in GA, or simply becoming inactive for medical reasons at any certificate level, increases with age. Commercial certs were still going up from the first dataset to the second.
It's interesting that the Boomers had a hard upswing in Student pilot certificates there on the last couple of lines. Pandemic and retirement may have spurred that. Also, Sport pilots in the Boomer age groups are increasing.
Total-wise, the decline is pretty steady from 2010 on out at around 31K per 5 years, but there was a loss of 20K from 00-05 and then a loss of nearly 50K from 05-10. That economy really wrecked a lot of people.
In any case, Boomers in 2020 still represented 27% of pilots, and about 23% of the population. In 2024, Boomers still represent 18.2% of active pilots, but the number of active pilots increased from 691,689 in 2020 to 848,770 in 2024

with the wave of youngsters chasing the pilot shortage. If we instead look at the number of boomer pilots vs the number of total boomers, it's gone from 0.384% in 2000 to 0.306% in 2010 to 0.244% in 2020 while the total population of boomers has dropped by about 8%. There's been some attrition of course, but only about 1/3 of Boomers have "exited the hobby" so far.
For sure.