That's an interesting point, and may very well be true. It doesn't imply that there's a correlation between age and stagnation, though.

Also, in my experience, stagnation can run in the other direction, temporally. I encounter many young people who won't even learn about, much less consider, using a tool like 'make', simply based on the assumption that newer seemingly similar tools must be better. Sometimes the old ways really are superior for the task at hand.

That's just it. It's really rare to find a 25 year old with a stagnant set of skills. I don't know if stagnation is the best word, but I also think there are other elements. Complacency in some cases, or getting too comfortable.

Most of the successful tech people I know that are 50+ never overstayed their welcome at companies where they stopped learning, or they were always being recruited by other firms and moved around. Recruiters generally aren't knocking on doors of someone who has been at the same company for 20 years, and that's for a variety of reasons.

We must move in different circles. I've tried to sell whole teams of 20-somethings to give git a try, and they're just not having it. They know what they know, and that's it.

I must move in different circles too. Every programmer today uses git, only maybe people stuck at a big company like Microsoft for their whole career don't use git and even Microsoft uses them now. And make: it's what everyone uses. Sometimes cross operating system projects use cmake instead of make but it's not that different. All the new programmers I meet coming out of college use these tools.

> It doesn't imply that there's a correlation between age and stagnation, though.

Not the way you're describing it. However, there's a pretty common correlation between age and relevance of skillset, which is a direct consequence of stagnation over many years.

The point is that someone saying "old == stagnant" may actually be thinking of it the way I'm describing, which has more validity.

Your first sentence is a loaded, presumptive opinion that assumes age equals out-of-date without evidence.

Younger ones can have all the latest Javascript library experience they want but they still don’t have enough obvious experience for engineering mastery that’s vital to being a highly-productive independent contributor or tech lead.

> Your first sentence is a loaded, presumptive opinion that assumes age equals out-of-date without evidence.

Read it again. It's referring to older stagnant people, not all older people. The longer someone has been stagnant, the more out of date their skills become.

We know that, but employers are looking for React.js developers, not Software Engineer Architect. Whatever you like it or not you need to have a relevant tech on your CV.