Looking at an interview roadmap for a bigtech company, and I'm pretty sure the sheer size and intimidation of it turns skilled people away from these companies. You need a specific mindset to participate on either side of this, one that prioritizes tech over anything else.
Their "what's next" emails even contain multiple page-overview on "how to succeed" with a dozen links and 40 bullet-points.
I am absolutely sure there was a D&I complaint identifying the issue, and the only way they could solve it is by adding guidelines for helping interviewees train better.
Which is wild and kinda highlights the issue, not solves it.
I've worked at a bigtech company and have seen how D&I suffers. "We had a goal to have more non-white employees, so this year 70% of our unpaid interns were from minorities! FTW!"
D&I is always a top management problem. I cannot be fixed from the bottom.