There is also the fact that with juniors training like pros, and pros being so young, the standard age progression is very hard to predict. Seixas has taken two massive steps from 2024 to 2025, and then again into 2026, but it's hard to know at what point the steps get smaller or stop. Of course, he might do another in 2027, or he this might be very close to the best he gets – who knows.
Or, it might be like Pogacar where the biggest jumps come a few years apart (at least in Tadej's career, 2021 and 2022 were very similar, and 2023 was impacted by wrist injury but the huge step up was 2024).