If you want to see the senselessness of Britain’s immigration debate play out in real time, look no further than the crackdown on care workers’ visas that came to a head this week.

As part of its plans to force low-paid migrant workers to wait 15 years before settlement in the UK, the Home Office has been in a battle behind the scenes for the past six months to controversially include care workers in the policy. This is despite the social care system already facing critical staff shortages and the number of British citizens and immigrants taking the jobs dwindling.

After a fierce backlash from health unions and Labour cabinet members, this week the home secretary, Shabana Mahmood, announced a partial U-turn: an estimated 280,000 care workers and their dependents will be exempt and allowed to apply for indefinite leave to remain (ILR) after five years.

It’s a welcome reprieve from a policy that should never have been on the table. But check the fine print and this “watering down” will not protect every care worker. Only carers who earn £25,000 a year and entered or switched on to the care staff visa route before the white paper’s publication in 2025 will be eligible.

Those who don’t meet the strict requirements will have to get another five-year “health and social care” visa before applying for ILR – a move campaigners are warning will leave vulnerable workers open to exploitation from unscrupulous employers.

Ministers have not established what benefit any of this is meant to bestow on the British people, millions of whom rely on migrant carers to help them or their elderly parents wash and dress. Nor has anyone explained how Labour’s upcoming care reforms will work while alienating – rather than actively recruiting – more international staff, as recent tightened immigration rules already have.

Or, to put it another way: the government has simultaneously pledged to fix social care while creating a hostile environment for the migrant staff who keep the system afloat. It sums up not only the nastiness of it all, but the deep-seated irrationality that now plagues almost any mainstream conversation about immigration, with politicians across the spectrum seemingly contractually obliged to ignore basic common sense as well as decency.

Few things demonstrate this more than the obsession with the “contribution v cost” framing that dominates these debates, and which Labour has now threaded through its visa policy. On paper, it appears to many a fair and logical way to allocate visa rights. In practice, it rewards the wealthy and dismisses the value of working-class and predominantly female labour: while care workers will have to wait five or 15 years for ILR, a solicitor on £125,000 can get fast-tracked in only three.

It is blatant classism, sure, but also fundamentally misses the very obvious tenet of capitalism that a worker’s “contribution” to a society and economy is not necessarily reflected in their wage packet.

That Mahmood has been doing the rounds in recent months using disputed figures to claim that granting ILR to care staff and their families for the next few years would cost the public purse £10bn over a lifetime suggests how unreliable – and outright ludicrous – the cost v contribution binary is. These are the people keeping our loved ones alive for the minimum wage and we’re still debating whether they’re a burden on the taxpayer.

Of course, evidence shows care workers are, to use that favoured phrase, “net contributors”. The Institute for Public Policy Research (IPPR) found this week that skilled migrants – including care workers – and their families due to settle in the UK under current rules are expected to boost the public purse by a staggering £115bn through taxes.

Such a figure doesn’t even include the many other ways care workers save the country money: by enabling family members to keep paying income tax rather than quitting their jobs to be an unpaid carer; supporting younger disabled people to get to the office and stay in work; or keeping older people out of expensive hospital beds by reducing their risk of falls.

And yet we are losing something if we accept the idea that a migrant’s “contribution” is only in economic terms, as if the Home Office can scan a human being at the border and put a price tag round their neck. Anyone who has ever relied on a good carer knows there is value that can’t be measured on a spreadsheet: the security of knowing there is someone to help you get out of bed in the morning; the dignity of having a regular shower; the laughter that comes with a shared joke as you write the shopping list together.

You won’t see many of these people on front pages or hear their voices on radio call-ins. But the people providing care and those who rely on it will “contribute” considerably more to the debate than the non-disabled white contrarians who so persistently dominate it.

If it is a “legitimate concern” for the public to worry about immigration, it is legitimate for a disabled person to be afraid there will be no one to help them cook dinner, or for a migrant to worry about where they’ll live next year.

Because here’s the thing about fears: some are irrational, and others are not. Labour would do well to remember which ones it should listen to and which it should challenge.