If "IT Consultant" is just jargon for staff aug, then it is true.
But if "IT Consultant" means someone who is called in for advice on the strategic direction of the enterprise IT plan, then it's not true.
Some years ago, there were maybe a thousand such people in the IT field. There are still some such people, maybe about a thousand of them. They are professionals, and for the most part, they get treated like professionals. They don't get hired through agencies, they don't work for one client at a time, and they don't become fixtures at the client site.
And their deliverable is advice, not code.
And, yes, lives do depend on the value of their advice.
Real consultants make themselves expendable. The client doesn't have to hire some chain-saw project manager to make them expendable.