No

As someone who maintains a container runtime, this whole idea is just ridiculous. While there are downsides to the split-out model of namespaces, all of the upsides are immediately lost when you suddenly decide to create a mirror interface that removes all of the benefits (and is also just ridiculous).

The complexity in runtimes is something that we've already made peace with. Why are you changing the interfaces underneath us? Who actually asked for this?

If you wanted to implement Zones or Jails on Linux, you should've just done that in the first place.