Which means Agile will always be more expensive, time-consuming and difficult than alternatives.
Say you're building a boat. Boats require not only lots of skills in woodworking, but a whole 'nother skill of design, to get a boat that does what you want on the water. It is always time-consuming, expensive, and hard.
And there's two basic ways to build it: with plans, and without plans. Without plans, you have to design it yourself, then try to build it, then make mistakes, maybe even to the point you have to start from scratch. Time-consuming, expensive, hard. But start with plans that have already been built, and you benefit from somebody else's time, money, expertise and toil. The boat is built faster with less effort and fewer mistakes. And instead of needing master craftsmen, you only need journeymen who can follow orders.
No, that's not at all what it means.
It means, that you need capable engineers, who are willing to talk to users and build understanding, rather than just being Jira task rabbits. It means, that you might not even need all the intermediaries, each having their own personal agenda and incentives, that engineers usually have to put up with. It also means, that certain layers in an organization have to trust their employees a little more.
It means, that what you build it based on user feedback, rather than what someone tells the engineers, what the user feedback supposedly is, without having a clear idea, what the users actually want. I have seen this first hand. When in the beginning of the product I as an engineer interacted with the users and found out their issues with the platform I was developing, later on the organization added hierarchy layers, shielding or preventing engineers from talking to the users, to build their own job moat, and patronization going on in terms of "Your time is better spent developing the actual features.". In the end the product ended up drifting far from what is good for the actual users, and instead people talked more to B2B customers, than the employees at those other businesses and what they actually need or want.
With each additional layer between the user and the developer (which is also people who want to be paid btw.), the business is inflicting significant cost and increases the risk to steer off course.