Age discrimination goes both ways.

For younger workers you have the chicken and egg situation of requiring experience without being given the chance. Or a minimum wage that is lower than someone older for doing exactly the same job. Or prejudice from older age groups regarding a 'woke' society and a misplaced notion that things are easier now.

Older workers have other concerns. The over 50's make up over 30% of the available UK workforce and as you near the end of your working career you worry about your pension and life affordability for your retirement. For most it is essential to be working and generating an affordable income from your pension. So when you find yourself out of work it is a stressful time at the wrong end of your working life which is then magnified by widespread age discrimination.

Like all prejudice there is no logic when it comes to to age discrimination. If you discriminate against another ethnic group you will never be part of that group. If you discriminate against a gender it's unlikely you will share that gender in the future. If you discriminate against people with disabilities, sexual orientation or religious belief it's possible, but unlikely, you will become disabled.

If you discriminate against employing older workers then you are discriminating against a future you. You will get older and be discriminated against. You will become an older worker and unless you become part of a change of positive behaviour towards older workers, you to will be discriminated against. 

Far too many managers, typically aged 30-45, reject older candidates for reasons based on prejudice. By rejecting the candidates they actively discriminate, which is illegal. 'Stuck in their ways', 'untrainable', 'will tell me what to do', 'be like managing my Mum or Dad', 'won't fit into the team', 'overqualified', 'too experienced', 'will get bored and move on', 'I wouldn't take this job at their stage of career' or 'I will feel uncomfortable managing them'.

When you go to the hospital to have an operation you don't ask for a less qualified surgeon. When you board a plane you don't want a less experienced pilot. You don't care why they are flying the plane or operating on your body, you just want a great job done. Age, like Race, Gender, Sexual Orientation, Disability & Religious Belief should not be a factor if you are competent and have the skills to do the job required.