The point isn’t that techies over 40 can’t do good work or keep current or invent the future, it’s that they can’t get a job.
As someone a few years north of 40 and recently went looking for a new job, I can identify with much of the article. Although for me, in the market I’m in, I kinda felt the pay for a ‘senior dev’ didn’t really cut it either. The whole pay structure is for younger folks and veterans have a hard job finding work.