Er, didn't this guy choose to apologize? I see no evidence that his job was at risk or he was at risk, just that people complained about a tacky shirt and he said sorry for it.
Isn't rushing to defend him sort of the essence of white knighting? The act of defending someone while simultaneously denying them agency.
He could have just as easily told them to stick their criticism up their fundament, he didn't-he said sorry. His decision, not anyone elses.