The income test would work - as in Australia - with an asset test as well. As with some other benefits, an imputed income from asset values can be used to show what level of income the assets should be generating. There’s no other way for it to work with the move now to DC pension schemes where withdrawals are flexible, otherwise people could continue to hoard assets and claim welfare they don’t need.
It’s not a very onerous assessment process and works fine in Australia. It’s well-established and generally supported by the public as a good system that supports the poorest and avoids wasting tens of billions per year on welfare to people who categorically do not require it. We can set the limits generously, there is a gradual taper not a cliff-edge. Unlike other tapers in the tax system it won’t have any statistically significant impact on economic growth at all because retirees aren’t working or starting businesses, on the whole. It won’t leave a single pensioner in poverty.
But no, pensioners should not be allowed to rattle around in a property 5 times the size they need at the public expense of paying their living costs when they could move to somewhere smaller and pay their costs themselves. Neither should they be able to sit on hundreds of thousands of pounds in savings for potential care costs (which only a small percentage will require) while living off the tax payer.
Care is precisely the kind of system which it makes sense to fund with a compulsory national savings model. I’d suggest that for the long-term alongside pensions there is a hypothecated amount that all employees or self-employed people are required to pay from earnings that goes into a specific fund for that individual, to save for potential care costs for the future (and that this amount - if unused - can be left free of IHT or other taxes to descendants so it isn’t used as another way to rip people off and they can see it is for their own benefit). This will avoid future demographic issues arising from a ponzi scheme system - pertinent given the falling birth rate. As for those already retired, I’m afraid it’s on them for not having reformed the systems to avoid the demographic time-bomb during their working lives, as the Australians of the same age did…
I would suggest NI on pension income is introduced for those who have already retired, and at a higher rate than the working population pay (to make up for the shortfall in taxes that they paid in working life) and applied to investment income as well as earnings/ private pension income, and that this specific money is kept in a separate fund and invested so that it will grow and used as a combined fund to fund care for retirees until such time as the system in the above paragraph comes to fruition so that everyone retiring has a significant dedicated personal care fund saved up.
Then the level of NI on pensioners can be gradually reduced as these personal funds taken over provision, obviously throughout with the state providing a backstop but only in cases where the person was either severely disabled and unable to work during their working life or has exhausted their personal fund.
Again, the solutions are long-term and won’t be palatable to the most entitled generation in history, but we cannot continue to have our young people’s futures (and those of all subsequent generations) destroyed just to please retirees who really like their 5 bedroom house which they live in alone. Like everyone else, if their assets are relatively illiquid and they don’t have enough money to cover day to day living costs then they need to take some responsibility and sell some of those assets and convert them into cash, not expect people who are, mostly, much poorer than they are to subsidise their living costs.