Checkout NSX-T installation guide. It supports other worlkloads besides vSphere VMs:
Bare metal servers: Bare Metal Server System Requirements
Kubernetes and Pivotal Cloud Foundry: Compatibility Requirements
Openshift: Compatibility Requirements
For micro segmentation of virtual machines the two platforms supported are vSphere and KVM (NSX-T)
Now, other platforms and physical servers can still benefit of NSX security features. Using features like L2 bridge and L2VPN you can more or less integrate these components into the NSX platform.
Not only vSphe and KVM but also Bare metal servers are supported as transport nodes in NSX-T according to documentation I already sent. I have tested it out and works well. You can even connect a bare metal server onto an overlay network.