It depends on what you want to know about that physical server
As you said, SmartState Analysis works by creating a Snapshot of a VM and analysing the contents of the file system, therefore this approach will only ever work in virtualized world.
MIQ does have a SmartState Analysis feature for linux containers. Containers are themselves static images, therefore the process skips the snapshot step and just analyses the image (I have not used this feature yet)
The point is: SmartState Analysis is everything introspecting a resource beyond, what the normal management tools provide, how it goes about is up to the technology involved
MIQ added a physical infrastructure provider for Lenovo XClarity in the latest release, therefore something is happening in this area, but I am not following it that closely
I guess the best you can do at the moment is to use Ansible to gather information from physical systems. It works for both linux and windows and only requires tools natively available (python for linux, powershell on windows)