"unconscious bias silliness" so you're telling me that an interviewer is just as likely to hire someone who has visible issues sitting still/focusing on a video call as they are someone who sits perfectly still and gives their full 100% attention to the call? No, not a chance. When there are two candidates for a position at approximately equal skill levels when performing a video interview but one has ADHD that comes along with the inability to remain solely focused on one small screen and voice for an extended period of time you can guess which candidate is going to be picked the vast majority of the time. Dismissing such a huge issue as silliness is exactly the reason why many people who have issues similar to that do not want to perform video calls for interviews.

Yes, unconscious bias is a silly thing to talk about when so many still people face outright discrimination and hostility, but I don't think GP meant unconscious bias.

The A/B studies are also used to prove discrimination that people usually won't admit to, not only to reveal unconscious bias.