A large part of design is validating whatever tool it is that they produce with the people for whom you're building it, and do it again at every step of the process with the intermediate designs - not just as a single upfront gathering of requirements. This is not something that you get from an eat-you-own-dog-food approach.
But when a company grows, I think of it like a sphere. The average distance to a customer keeps increasing. At the beginning, most people have contact with the outside world. But when it's large, most people's lived reality is about other people who work at the company.
And historically, that worked fine for large companies for quite a while. They were doing relatively stable, simple things that could be easily scaled. But things are hopefully changing. There are a lot of people who have spent their lives inside of large companies. Whatever it takes to rehabilitate them is fine by me.
if a company treats their (low level) employees like replaceable cogs, and never involve them in decision making, then yes, this does seem like a revelation!
However, this just goes to show that having trust, and empowering employees to be more autonomous and self-directed (with the appropriate amount of compensation based incentives of course) will achieve the same kind of results imho.