It could also be that they might be sued for stating the real reason so they went with something that would be dismissed if it went to court.
A little while later, the same company reached out and encouraged him to apply again. Five rounds later, and he got passed over a second time.
Fast forward two years and they reached out to him a third time. He's basically convinced that because he's black he's their token DEI interview candidate to make them feel better about themselves while internally promoting the people they actually want, but of course they wouldn't actually say that.