The time it would take out of your life (just because you hire lawyers doesn’t mean you’re spending no time on the lawsuit). And once you file that lawsuit it’s going to become public record that you sued a company you interviewed for, so there’s a lot of downside risk for the rest of your career. I understand the fear but I don’t think there’s realistically a lot of downside risk for employers to responsibly share some feedback. And certainly there’s no legal risk to just letting candidates know they went in a different direction.