In vSphere 7.0, it is possible the HA VIBs might be removed in some cases when HA is activated on a Lifecycle Managed (vLCM) cluster. In previous releases, vCenter would not attempt to remove HA VIBs from ESXi hosts.
This situation can occur only on vLCM clusters with vSphere HA activated. When a vLCM Remediate operation occurs (either as a user-initiated operation or an API invocation) after vSphere HA is deactivated on the cluster, the vSphere HA VIBs might be removed as a consequence.
Note: This change in behavior is harmless because vCenter pushes the required vSphere HA VIBs when HA is activated again.