The problem starts much earlier than the staff appointment stage. We have never had a Black person apply for a post in my department. Even when we advertised a post which specifically asked for a specialism in a Black studies area. I would be interested to know how many Black students there are in the top universities (which is, realistically, where academics are likely to be appointed from), because in my experience it is a tiny number.
I agree that the career trajectory in academia is massively classist. It requires years of insecure employment, poor pay and moving around the country from one short-term contract to another before the holy grail of a permanent of a permanent job is reached (and then it is only 5% of PhDs who end up in such a job). It favours people who have family support and lots of self-belief. That will never change because the kind of structural change required to make academic careers achievable for those from less affluent backgrounds will cost significant amounts of money that universities prefer to plough into senior management salaries, new vanity project buildings and other kinds of cosmetic enhancements to the “student experience” (a term which, interestingly never seems to get that teaching is important to the university experience) that look good in marketing materials.