I don't follow the difference between static and elastic workloads. OpenStack can create a VM just like VMware, and has more features that would otherwise be implemented as a K8s cluster running on VMs.
Elastic workloads typically scale horizontally, unlike the vertical scaling or static provisioning seen in environments such as VMware. Elastic workloads are usually stateless, declaratively provisioned, have short uptimes, and are designed to fail gracefully rather than relying on high availability.
Kubernetes (K8S) can achieve similar capabilities, but is still distinct from what OpenStack offers: an open-source, private AWS providing multi-tenant, API-driven infrastructure for storage, networking, and compute.
If you don't care about working with elastic APIs, OpenStack/AWS is probably not for you, use VMware/ProxMox + Kubernetes.