For me it's 3 main things.

1. The way historical oppression can set a group behind another group even after any specific policy has been repealed.

Poverty is often a cycle that can go on indefinitely for generations especially depending on things like upward mobility which has coincidentally been getting weaker since the period of official apartheid ended in the USA. Strange that we seem to be uninterested in spending much on the uplifting of our people now that such spending would need to include all people.

2. The way that bias against a group can result in that group being disadvantaged despite there being no rules or laws in place that require that and even in spite of it being contrary to policies.

Like the way that black people are half as likely to receive a callback for a job interview as an identically qualified white applicant or that despite being less likely to be found with contraband black people are twice as likely to be searched by police.

3. Would be laws and rules that do not target racial groups, but unfairly benefit or disadvantage racial groups.

This would be local property tax based school funding resulting in poor neighborhoods getting inadequate funding for schools resulting in predominantly black schools being underfunded. This is also drastically harsher penalties for crack compared to cocaine.