The goal was to bring Plan 9's most useful tools to Linux, rather than modify Linux to become more Plan 9-ish. Glendix doesn't modify the core or essence of Linux in any meaningful way (it's more like Wine in that sense), so the question of removing the root user never came up.

Couple of sub-projects within Glendix that are pretty interesting though are the synthetic /net filesystem that serves a TCP API, and per-process namespaces. These are simply in addition to what Linux already provides, so they don't impact existing Linux applications in any way. Glendix runs just like any other Linux installation, you just have access to more Plan 9 stuff.

The root concept is replaced by capabilities (sort of). So, for instance, the process owner that boots the machine (usually called bootes) can kill processes and spawn new ones as any username. That doesn't mean that they can fake your credentials to the network though, you need to authenticate with the auth server which will be on another machine. That you can access your files on the fileserver.

The concept of a network of connected islands is replaced by a network of connected services.