Tell you what, why don't we get rid of management altogether and just have a flat org ?
https://hbr.org/2013/12/how-google-sold-its-engineers-on-man...
With a USB stick and FTP. It's very easy to underestimate a problem when you've never encountered it or tried to tackle it in practice. Your shallow dismissal gives that away and brings no insight.
Human beings will always organically organize hierarchically. In a group one will have more initiative, one will be happier to be told what to do, etc. In the end informally you will end up with the same structure. And it's hell to deal with that when formally all have the same authority so none can override each other, but one guy just gathered enough support to do whatever he wants.
Do you think someone far away from everything you do will have a magic "workflow" that tells them what to do about the budget you requested, about the strategic decision you need, or about your conflicts, about who has to do the nice jobs or the shitty ones? And why would they have any say, they're not the boss.
Your logic is no better that those pretending today that a team of AI agents "with good workflows" can just replace all the programmers.
Valve the "game" company, has a relatively flat structure from what I've heard, and it's working pretty well for them, but they've also had it for a long time.
So if you have a company, that works like that from the start, that people know it works like that, that it has support for it. You could make it work.
I agree that forcing this structure everywhere wouldn't work, some people can work like this, others can't.
Valve has ~300 employees and operates in a field where they can afford more freedoms (try building large infrastructure projects with flat structures). Valve struck a good balance between autonomy for employees while still having some informal central coordination. Formally there are few bosses but in practice project managers and some people with seniority also act in those roles. At scale it can't work if you don't delegate any of the authority to smaller units.
It's bad to have too many or too few layers. Sometimes the result looks the same, lack of coordination and inability to deliver consistently.
Amazon has 1.5M workers. Can't imagine a flat structure working but I'm sure they were overdoing it with layers of management.
Because no one person is good at everything, and even if you managed to build a team of people who were good at everything, it is inefficient to make everyone keep up with all details of every aspect of the company so that they can be productive in an arbitrary role at the drop of a hat. Giving people a role allows them to specialize their knowledge and concentrate all their efforts into their area of expertise/competence.
Managers fill a role. Sure, some managers are bad, and some workplaces have seemingly mostly bad managers, and it leads to cynical opinions about how managers are busy-work-making dolts who don't understand anything. Some employers have mostly good managers and I feel sorry for you if you have never had the experience.
I'm 40 years into my EE career and I have always deflected efforts to make me a people manager or a project manager. I like being a grunt in the trenches solving problems at the bottom level, and a good manager increases their reports' productivity by shielding them from needing to deal with project management crap. I would have retired already except I've been blessed to have good managers for the past 20 years, while my managers have been attending umpteen resource allocation meetings and all the attendant report-making that requires.