Just 22 percent of techies in UK aged 50 or older: Chartered Institute for IT

I might be inclined to agree if the same held true in other "professions" but it does not.

Based on personal experince in the USA, the half life of a STEM career is about 10 years. Every ten years, half the qualified "professionals" at this experience level have left the field --- either by choice or otherwise.

This doesn't happen to a similar extent with doctors, lawyers or accountants. Have you ever seen any public service announcement encouraging young people to study law or medicine? The tech industries are different --- they are dependent on a continuous inflow of young, naive talent to be burned out and largely discarded by middle age.