In 2022, the MLB average age of a fWAR was 27.8 years old. In the 2053 BBA, the average age of a WAR was 30.4 years old. Brewster batters are, on average, two and a half years older than the baseball players we watch on TV.
The shape of the aging curve of the BBA compared to MLB is strange (and even MLB has a couple weird blips).
The average MLB pitching fWAR was 28.8 years in 2022. Brewster pitchers averaged 28.9 years per WAR in 2053. In MLB, the offensive players were exactly one year younger than their pitching adversaries. On the ther hand, the much older batters in our league are succeeding against typically 1.5 years younger--and by assumption inferrior--competition on the mound.
The pitching curves are more similar.
