I was thinking the opposite. Until the last 15 years or so, most pro riders had stopped racing by age 33 or 34 at the very latest. But Mark Cavendish won his last Tour de France stage at age 39, Alejandro Valverde was winning stages in the Vuelta a Espana at 41, and Chris Horner won the Vuelta at 41. Geraint Thomas was still competitive at the highest level when he retired at 39. And Davide Rebellin continued racing until he was 50!
Yeah, good point!