I have always been good at learning new languages / frameworks, but I see his point: when I work with older programmers, most of them are indeed a bit slower to adapt, and have a harder time learning new concepts (like Observables in Javascript).
But I am very happy with what I do now. I love being given technical challenges and solve them ; I don't want to manage teams or write documents about architecture. So I'm asking you, especially the senior developers out there: do you see yourself struggling to keep up as you grow older? Is staying "competitive" more challenging? Do you regret not taking more responsibility or do you still love being "just" a programmer?
Thank you all very much for your insights :)
In workplaces where these roles are not recognized older developers tend to become grumpy and do not contribute much more than the others.