Please explain how you can put an entire system together that way in a non stupid way.
are all incredibly cheap when compared to human effort in dependency management with dynamic libs. And most Linux packages managers don't elegantly support installation of multiple versions of libs (libfoo and libfoo123 isn't elegant). The way you'd fix that is similar to what the OP is proposing.
Of course, there's many other concerns: but it's not entirely unreasonable.
One working example of this type of system is RacherOS[1] which I think could do what I'm proposing. I'm excited to see it mature. People can just package their app in a minimally sized container and be done with it. I think it's what the linux community really wants anyway (modularity and options) but adds the ability to switch without re-installation from scratch.