I want to tell you about two very different disabled people, both going through Britain’s benefit system.

“Disabled person 1” has Parkinson’s disease and terminal cancer. The effects of the Parkinson’s are so severe, he’s about to undergo brain surgery in attempts to mitigate them. Still, he had his benefits stopped after assessors decided he was no longer ill enough for personal independence payments.

“Disabled person 2” has fibromyalgia – “Like the Incredible Hulk grabbed me, lifted me off the floor and flung me against a brick wall” – as well as a host of other conditions. For years she has bounced round the benefit system: tested, rejected, overturned at appeal, then tested again. Now she’s about to be re-tested twice in the space of three weeks: once for PIP and then for her out-of-work sickness benefit, employment and support allowance. It means she could potentially lose all her income at once. “So what will I live on?” she says. “More to the point, where will I live? Once they cut ESA, that means rent will stop too. That means eviction and homelessness.”

One of the two disabled people had their story picked up by sympathetic national newspapers this week, with broadcast journalists also respectfully discussing their plight. The other sent their story to me in the early hours of Saturday morning. She had already contacted her MP but with little hope of reply, she wrote to me too.

The difference? The first was a high-profile former civil servant, Andrew McDonald, who spoke out at the weekend over what he described as the “hostile environment” created by the system. The second was an ex-IT worker with no connections, struggling to get by on benefits.

It is not surprising that the experience of a former high-ranking civil servant would gain media interest and McDonald’s case deserves attention. But the double standards can’t have escaped many disabled people’s notice: if McDonald fitted the mould of a typical “benefit claimant”, he would likely have found himself experiencing a very different reception by the media. What thousands of disabled people in poverty have been saying for years about the “Kafkaesque” benefit system is apparently credible and important now a middle-class senior official is saying it.

It reminds me of the Grenfell victims, who warned before the fire about the safety risk of the cladding but were ignored as poor, migrant, and black people; or the women who talk relentlessly about sexism but it’s only when a man says it that it’s seemingly worth listening to. It is not enough to speak out about the harm being done to you. You have to be the sort of person those in power want to listen to.

Andrew McDonald. Photograph: Andy Hall/The Observer

Britain’s benefit system runs on a sort of institutional gaslighting, in which disabled and poor people are simultaneously pushed into starvation, homelessness and mental health crisis, while their hardship is either repeatedly ignored or openly vilified. Think of the rightwing headlines distorting stats to bemoan “sick note scroungers”, or the way some privileged commentators mocked the realism behind Ken Loach’s I, Daniel Blake. It is not for lack of evidence; be it the rates of successful appeals (at last count 70%) or the behaviour of assessors, report after report backs up disabled people’s accounts of ill treatment by a social security system that is meant to help them.

For an insight into the toxic culture of disbelief “welfare” claimants face, research this week found that almost half of disabled people fear being stripped of their benefits for being “too active”. (If this fear sounds far-fetched, disabled people are routinely falsely reported for benefit fraud to the authorities for even going to the shops.)

A report by the Equality and Human Rights Commission to the UN this week warned that one in five disabled people are suffering “erosion of their rights” because they are disabled, and this can’t be seen as separate to the downplaying of disabled people’s suffering in the benefit system.

Given our place in the economy and society – as more likely to be in poverty, unrepresented and excluded – most disabled people have few means to influence debate or change policies. I’m writing this as one of the few disabled columnists working for a national newspaper. It’s not a coincidence that a media – or parliament – that is widely made up of white upper-middle-class non-disabled men don’t naturally listen to the voices of poor and disabled people. It’s surely an in-built bias as much as wilful exclusion: people are largely socialised to put less value on a person’s life and voice if they are black, disabled, female or poor.

The fact McDonald had been a senior civil servant but only became aware of the reality of benefit policy once he was affected, and the media’s reaction to it, are both clear arguments for better representation of marginalised groups in power. Get more people in positions of influence who actually experience the brunt of the policies being brought in, and these issues would be more likely to be addressed.

It’s hard not to think that if officials were on the social housing list or applying for universal credit, council homes would be plentiful and assessments would be humane and competent. As it stands, the McDonald furore shows not only how broken our benefit system is, but something altogether more disturbing: some disabled people are just worth more than others.

• Frances Ryan writes the Guardian’s Hardworking Britain series