I think you may misunderstand the point of a consultant. Generally, a consultant is an expert in some field that a company hires so they can get questions answered. Sometimes that expertise is in things like sensitivity feedback or diversity/equity/inclusivity, but it can also be in any number of fields - corporate efficiency, a specific type of technology, economics, ancient Chinese history, military tactics and equipment, constructed languages, skateboarding physics, or (in Darrah’s case) extensive brand knowledge and experience.
Companies hire consultants, often for very high fees, to answer the questions they need the specific expertise for. If a company or a person has questions they absolutely need answered, they’re often willing to pay an expert to answer them. The most common situation for regular people to hire a consultant is when they have legal questions - they usually hire a lawyer to ask them the questions and get answers. A game company might need questions answered about reducing sexual harassment in the workplace, how ancient Mayans farmed, or how the Battle of Bulge went down in order to finish their project.
Relationships with consultants are usually fairly short affairs - once the necessary questions are answered and solution is decided upon, the consultant gets paid and they leave. They’re very similar to contractors in that way - they are paid to join the team temporarily, do a specific thing (answer questions and/or come up with solutions), and then leave. You may have noticed that this blog is basically a (free) consulting gig for me. I’ve got a lot of institutional knowledge that isn’t super common and that knowledge is valuable. If a company wanted my expertise to help solve a specific game development problem or answer specific game dev questions, I would charge them a consulting fee for it.
Got a burning question you want answered?