Chewbacca The number of jobs in the economy is not fixed and in a successful economy is continually growing. So this idea that the old should retire to make way for the young is fallacious, anyway if the old all retire the taxation on the young goes up to pay for the pensions.
When the pension age was set up at 60 for women and 65 for man, life expectancy for those reaching retirement age was well under 75. On that basis the age for receiving the state pension should now be 75 or thereabouts.
Anyway this tired old argument has long currency and has been used to justify sending wmen back into the home (taking the jobs that should go to men) and immigrants, and that quite recently, (send them back they take the jobs and reduce the wages of decent white workers). Many people work because they want to and because they have skills younger people do not have.
The rapid construction of windfarms currently owes a lot to people like DH, aged 77 and many of his previous work colleagues, who are still working and have transferred their decades of experience moving oil and gas platforms around the waters off Britain and Europe to moving wind generators offshore. As the offshore oil industry has slowed down over the past decade, the youngsters just do not have the experience.