What about all the 50 year old engineers who have been made redundant and are finding it hard to find work? A combination of this and wanting a sense of purpose could make this an attractive proposition. Also I think forcing someone this experienced to follow the junior associate track is not a good system. Surely there is a better alternative way to leverage the technologists knowledge snd experience. It's exactly things like this that I expect to be discussed here.
Stop looking for a jobs at all of the cool startups and look for boring corporate jobs. I’m 44 and never have any issues finding jobs and know plenty of 50 year old developers. The difference is that we are all aggressive about keeping our skills current.