what are they talking about product teams needed to justify themselves? a good product guy's job is to talk to the users and figure out what to build. My job is to figure out HOW to make it happen. Neither side need to justify themselves. Good product people are vital to making sure engineers don't spend months building the wrong thing.

Where are they getting this absurd notion?

A lot of engineers find it difficult to conceive of product and design (and marketing, and management…) as actual skilled work. It’s all con artistry orbiting engineering.

Con artists do tend to be skilled.