The RHV Hypervisor is not limited by a fixed technology (or marketed) restriction. Red Hat lists no Limit for the maximum ratio of virtual CPUs per host.

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Virtualization_Deployment_and_Administration_Guide/chap-Overcommitting_with_KVM.html

In reality the specifications of the underlying hardware, nature of the workload in the vm and the overall restriction of 240 logical CPUs per host will determine the limit. RHV has been publicly demonstrated (see SPECvirt) to run over 550 VMs with a mix of SMP vCPU VMs.