I mean, writing code is a big part of the job? I bet they asked behavioral and system design questions too, even though I'm sure he solved business problems and designed systems in 8+ years at FB. Why interview in the first place, why not just give him an offer up front?

Interviews aren't fun, but there's not something "wrong with the industry" if the questions are relevant to the work. He even complimented their choice of programming questions.