And the expert on boilers is probably a 50-year-old dude who repairs them for a living and who you can only find by word of mouth, not a 25-year-old just out of college with flashy pitch decks and pristine Gucci loafers.
Ultimately, a consultant is whatever you hire him to do. Sometimes that means listening to what they have to say (boiler expert, lawyer, etc.), sometimes that means having them listen to what you have to say. The 25-year-old in Gucci loafers is happy to do the latter.
Yeah if you hire a big 4. My consulting team is all people with actual industry experience ...