The proportion of black students at Russell Group unis is around 4%, roughly half of the proportion of black people in the 18-24 age range. Black students have higher dropout rates and are less likely to achieve first or second class honours. Black STEM leavers are more likely to be unemployed [0].
Black people in the UK are more likely than any other ethnicity (including white) to be living in a deprived neighbourhood [1]. Nearly half of households with a black head of household are in poverty, compared to 19% for whites [2]. Similar trends are reflected in London [3].
[0] https://royalsociety.org/-/media/policy/publications/2021/tr...
[1] https://www.ethnicity-facts-figures.service.gov.uk/uk-popula...
[2] https://irr.org.uk/research/statistics/poverty/
[3] https://trustforlondon.org.uk/data/poverty-and-ethnicity/