Software development is different than competitive programming, and while it's true that there's performance degradation with years it's either not meaningful enough for the average software project (or as meaningful as they think), or it's counterbalanced with experience, because there's more to developing software than writing code.
But I'm a career switcher (waiter to software developer) who made the switch when I was 40, meaning I'm obviously against ageism.
Very apt distinction of being a software engineer vs other things. Not everyone has to learn Rust and write a new compiler
One can manage their expectations from programming by aiming to learn to code and only work with high level languages and develop software than do low level coding.
But I'm a career switcher (waiter to software developer) who made the switch when I was 40, meaning I'm obviously against ageism.