@Heatpumphero
"The only people getting a state pension in the future are those who need it. You’d be a fool to do otherwise."
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Whilst I don't disagree with you on the need for future means testing of the state pension, actually having it as a political policy would be electoral suicide.
Plus there are a lot of workers who simply cannot afford to pay in to a private pension (not necessarily fools) and a lot of workers who can afford to pay in to a private pension but choose not to (fools?).
The point is means testing state pension would create a perverse incentive not to pay in to a private pension, especially when the state pension is triple locked.
So who is the fool? The person that pays into a private pension but then disqualifies themselves from a favourable state pension or the person that either spends the money or saves it in non means tested wealth so they can still qualify for a state pension.
But as you rightly point out this doesn't change the fact that economically it will still become unaffordable for the Government. But given that older people are more likely to vote than younger people no political party would dare to mean test the state pension. Look what happened to Theresa May when she wanted to means test Winter Fuel payments.
Politically it is far easier to finance the state pension by cutting spending on education (young people don't vote), although this does have a big negative impact on future economy (but hey that's another politician's problem).