[fjp]

I think when people talk about this, they mean to push back against the fact that people will often to be biased to hire someone they think they could be casual friends with, share interests with, etc.

I like my coworkers and I find them perfectly find to work and make small talk with, but I don't share interests with many of them and wouldn't really care to hang with them outside of work. That shouldn't be a criterion for hiring.

I have found it highly annoying to work in engineering orgs where everyone seems to have the same interests. Everyone talking about Star Wars, Dungeons and Dragons, Lord of the Rings, etc. constantly because it's assumed everyone else around also enjoys that conversation.