eemingly brilliant conference speeches are often followed by a hangover, and so it has arguably proved with Andy Burnham's. It was, it has to be said, something of a triumph, but there is now a familiar sense of nagging angst over how his big idea of a national care service is actually going to work. But equally, it doesn't seem unreasonable to be more generous and patient. The policy issues are vast. The new PM's commitment to serious change is clear. And having been urgently needed for years, the basics of what he wants – personal, home-based care delivered free at the proverbial point of need – will be on their way if Labour wins the next election.

Here, though, is a question that is much less finely balanced. Neither Burnham's speech nor the much shorter address given by Yvette Cooper, the new health and social care secretary, contained a single mention of what roughly half of England's social care budgets are spent on: provision for working-age disabled adults. Why not? I get the politics: fixating on older people's care and the pensions triple lock makes everything clear and relatable. But England's fragmented, unreliable system for younger disabled adults is in need of the same radical level of reform, and it's the source of just as much fear and worry for the people who either depend on it, or eventually will do.

I am one of them. In fact, I suffer from two sub-types of what we might call Care Dread. My mum is 83, my dad is 90, and they currently pay for visits from domiciliary care workers whose frequency is only going to go up. My son James – who is autistic and has learning disabilities – has just turned 20. He currently goes to a brilliant further education college, but my partner and I will soon face what special needs parents call "the cliff edge": a switch from education to adult social care, which will bring on a bucket-load of questions. Could he be helped into employment? If he stays at home, what support and everyday stimulation is our local council going to pay for? If he goes into supported living, how do we guard against what I have heard about from other mums and dads: long days spent plonked in front of the TV, the odd trip out, and the possibility of housemates with completely different needs?

The list of fears goes on; it haunts all parents in our position. A new focus of worry, moreover, has just been added: proposals to axe the health element of universal credit (which has already been almost halved this year to £217 a month) for young people with disabilities and health issues, and replacing it with new work schemes. To quote from the Guardian's report, that plan comes with assurances about the measures not applying to "those with the most severe and debilitating disabilities", which rather implies the grimly familiar official belief that you can easily grade disabilities from "mild" to "profound", when lots of conditions show that you can't (autism is one good example). But the proposals also underline why social care for disabled people has to be a big part of whatever detailed plan Burnham, Cooper and their comrades come up with.

We know that the crossbench peer Louise Casey's independent commission on adult social care has been convened to consider both older people's care and support for working-age disabled adults. But evidently, the government is much keener on talking about the former than the latter. Indeed, when I contacted the Department of Health and Social Care, I was sent a comically bland and noncommittal response: "The prime minister has made clear that he wants to see rapid progress on adult social care reforms … Baroness Casey's commission will outline what a national care service should look like, and as part of the review, the commission will explore and consider the options for supporting working-age disabled adults as well as older people in need of care."

Jim Kane is the CEO of Community Integrated Care, a not-for profit that seeks to provide supported living and residential care for about 3,000 autistic and learning-disabled adults. "People who have disabilities absolutely have to be front and centre of everything that's discussed," he told me last week. "But I also want to be supportive of what the PM's trying to do, because I don't believe in my heart that he's going to ignore disabled people."

There is so much to put right. Even in cases of disabled people who rely on benefits to live – the personal independence payment and universal credit, mostly – many councils' care systems subject them to a means test. That means they snatch money as a contribution to the cost of care, whether that's received at home and in what officialspeak calls "the community", or through supported living. The learning-disability charity Mencap alerted me to the experience of Fred – who has Down's syndrome and autism and is deaf– and his mum, Annabel, who live in Somerset. "What many people do not realise," says Annabel, "is that the local authority charges Fred £147.54 a week from his benefits to pay for his care. This leaves him with just £201.56 a week to live on, which amounts to £10,481 a year."

Two other issues were explained to me by Alison Bloomer, the editor of the expert online magazine Learning Disability Today. First, hundreds of thousands of disabled people are on waiting lists for the initial care assessments that councils endlessly evade and delay. At the moment, for people up to the age of 25, the special educational needs and disability (Send) tribunal – where decisions can be appealed – and education, health and care plans, which set out the support a young person is entitled to, offer some means of challenging councils' decisions and conduct, though the government still seems set on degrading both mechanisms. And this is her second point: that dependence on the social care sector, by contrast, means the weakest kind of accountability. If you have a grievance, your only real hope is either the local government and social care ombudsman or your MP.

In his speech, Burnham made moving reference to "the care we give to each other" via the state. But how do we define that? If my son starts to live within the care system, will he still get to indulge his passions: the Strokes, guitars, hillwalking? As Kane put it: "The social care system deals in safety. Have people got a roof over their heads? Have they got food? That's about it, and it doesn't even do those that well sometimes: we've all seen the scandals. How does it help individuals build relationships? Can they even choose the people that they live with? You know, 'Who are my friends? Can I have education? Can I pursue my hobbies?'"

The chances of a system being able to consistently meet such fundamental needs are made slimmer by the appallingly low pay rates of care staff (the government is moving on this, although progress towards an adult social care fair pay agreement is still ongoing). Kane would like his employees to be thought of as the equivalent of Band 3 workers in the NHS. But there is now a 28.6% gap between the two groups, and he cannot close it because of the dire financial position of just about all councils.

These are the deep issues that any credible national care service will have to solve. Furious disabled people's organisations are calling for a National Independent Living Service to be at the core of the reforms, but that will only happen if these issues are talked about – not just on conference podiums, but in the kind of Treasury circles where the best of intentions can too easily wither away. "If we want people to live genuinely fulfilled lives, there's a price tag that's different to the one we've got now," Kane told me. Such is yet another quandary faced by this embattled but confident new government, and a vivid reason why so many of us have to keep on pushing.