So just the managers and supervisors left then?
Whether the new policy will work out in the long term remains to be seen. I believe I read that Google tried a flat hierarchy for a few months and found that it did not work quite how they wanted.
Also, what will Tony Hsieh be doing in the new managerless structure?
Writing more 5,000 word emails?
"In 2002 they experimented with a completely flat organization, eliminating engineering managers in an effort to break down barriers to rapid idea development and to replicate the collegial environment they’d enjoyed in graduate school. That experiment lasted only a few months: They relented when too many people went directly to Page with questions about expense reports, interpersonal conflicts, and other nitty-gritty issues."
[0] https://hbr.org/2013/12/how-google-sold-its-engineers-on-man...
Once you grow beyond a certain size, you have to have people who function as communication hubs to deal with the n^2 connections between employees. The hubs end up consolidating power, and then you have management. There are probably ways to limit this, rotating managerial duties and such, but it's much harder than just adopting a hierarchical structure.