Earlier quoted context omitted.
>>75% - one year's experience 30 times, not 30 years experience. You don't want these people. You are basically saying 75% of the developers after certain age are useless. I don't agree or disagree with your statement . Just startled. What does it say about software development as a career ? Would you say the same thing for lawyers or doctors with 30 years experience? This is depressing.
I'm 47* and I've been around a bit (dotcom era startups to banking and telecoms) and I'm familiar with the 75% mentioned. There is a type of programmer that works away in blue chips turning up to work on time, doing what's asked of them and then knocking off at half five. Sure they maybe repeat the same one year's experience year after year perhaps with some technology transitioning years from COBOL to VB to VB.NET o…
I'm skeptical of the "financial security" claim. Obviously this is not true in the U.S., where there is zero hesitancy to lay people off and very rare to have legal recourse as an employee when laid off.
But even working in the U.K. or other nations with stronger worker protections, you are still vulnerable to your employer hitting hard times. Companies can very quickly go from profitable to out of business or close to it, especially where technology is involved. Not having skills applicable outside of your current job does not seem like a secure strategy.