Brexit divisions in UK society appear to be as entrenched as ever, according to the latest British social attitudes survey, with little sign that the issue is losing its polarising force. Nine in 10 of leave and remain voters said they would vote the same way again, it found.

Although Britain’s departure from the EU pushed overall public trust and confidence in government to its highest level for more than a decade, the survey reveals that this surge in support for the UK political system came almost entirely from leave voters – with remainers as disillusioned as they were previously.

The survey co-author Sir John Curtice said the latest findings contained little to indicate that Brexit wounds were healing. “As a result, Britain is left divided between one half of the country who now feel better about how they are being governed and another half who, relatively at least, are as unhappy as they have ever been.”

The annual poll is Britain’s longest-running tracker of public opinions, building up a comprehensive and authoritative picture of how the country’s attitudes and expectations have evolved over the past four decades across a diverse range of moral, social and political issues.

The survey found that the pandemic pushed public concern over inequality to its highest level since 1998, as well as raising support for welfare benefits and public spending, but it concluded there was little evidence so far that Covid had proved a “reset” moment that indicated widespread desire for radical social or political change.

The rise in support for progressive views on these issues was an extension of existing changes over several years rather than an abrupt shift in attitudes caused by Covid. “These trends do not signify a new direction in the public mood. Rather, in many ways the pandemic has reinforced opinions and attitudes that had already become increasingly common in Britain in recent years,” said Curtice.

Nonetheless, there was a sharp rise in 2020 in the proportion of 18- to 44-year-olds who thought Britain was unequal and favoured the rich. Younger adults were also more likely than older cohorts to agree that the government should redistribute income from the better-off to the less well-off – and this could have lasting effects, the survey said.

“It may be that the exposure [young people] have had during the pandemic to relatively high levels of precarity in their early adult years will prove a formative experience that leaves a legacy of a more egalitarian generation – only future survey research will affirm whether or not that proves to be the case,” it concluded.

The most recent poll of 4,000 British adults was carried out by the National Centre for Social Research between October and December 2020, with an additional survey of 2,400 adults conducted in July 2020.

Getting Brexit “done” had marginally reinvigorated overall trust levels in the UK political system – which had hit a record low in 2019. But this mainly reflected a major shift in the attitudes of Eurosceptics, who were for the first time more likely than remainers to agree that “governments put the nation’s needs before party interests”.

The reversal of some of the damage to trust in government caused by Brexit deadlock “might be regarded as a development to be welcomed” if democracy was to function effectively, the survey said, though it added: “Restoring the trust and confidence of remain voters looks as though it is still very much a work in progress.”

While few respondents who voted in the 2016 referendum appeared to have changed their view in the intervening five years, there was evidence of a shift among those who had not participated. More than twice as many (43%) in this group said they would now vote remain rather than back leave (18%).

Trust in government had been in decline for decades, the survey said. In 1987, 47% of respondents said they trusted government to put the needs of the nation above party interests “most of the time”. This slid to a 15% low in 2019 amid parliamentary wrangling over the UK’s exit from Europe, before recovering to 23% in 2020.

This recovery, however, was largely on the back of leave voters, 31% of whom expressed trust in government, up from 12% in 2019. Remain voters largely distrusted government in 2019 (14%) and this view had changed little (17%) a year later.

The debates around inequality sparked off by the pandemic caused a small shift in public attitudes. Nearly two-thirds (64%) agreed that “ordinary working people do not get their fair share of the nation’s wealth” – seen as a proxy for levels of concern over inequality. This was up from 57% in 2019, and the highest level since 1998.

However, this was not accompanied by markedly increased support for the redistribution of wealth from rich to poor. The survey found that 46% agreed with redistribution – up from 39% in 2019 – but the number disagreeing increased too, from 27% in 2019 to 30%.