This is not true. In fact, most people getting dialysis are over 65.
https://www.renalreg.org/wp-content/uploads/2014/12/Incidenc...
> Kidney disease is more common as we get older, and although people of all ages can need to start dialysis, it most commonly affects people aged between 65 and 84 years. Figure 2 shows the number of people starting dialysis or going straight to transplantation in each age group and it can be seen that the age group with the most people was 65–74 for both haemodialysis and peritoneal dialysis. In 2013, the average age of people starting treatment was 65 years and this has changed little over the last six years. The average age at start was 67 years for people starting on haemodialysis, 60 for people starting on peritoneal dialysis and 50 for those having a transplant before they start dialysis. In 2013, more men started treatment than women (63% male versus 37% female). Diabetes was the single most common cause of kidney failure (25%).
Here's a document talking about cost of dialysis for older people: https://academic.oup.com/ndt/article/18/10/2122/1807737/Cost...
The NHS Constitution for England forbids discrimination based on age, as does the Equality Act 2010.
https://www.gov.uk/government/publications/the-nhs-constitut...
> The NHS provides a comprehensive service, available to all
> It is available to all irrespective of gender, race, disability, age, sexual orientation, religion, belief, gender reassignment, pregnancy and maternity or marital or civil partnership status. The service is designed to improve, prevent, diagnose and treat both physical and mental health problems with equal regard. It has a duty to each and every individual that it serves and must respect their human rights. At the same time, it has a wider social duty to promote equality through the services it provides and to pay particular attention to groups or sections of society where improvements in health and life expectancy are not keeping pace with the rest of the population.