In Aria Operations 8.17.1, after enabling CIS Compliance module you do not see ESXi Host Compliance objects in the object breakdown section. The object breakdown section shows only these three entries: vSphere Distributed Port Group, Virtual Machine, vSphere Distributed Switch.
When we try filtering the alerts definitions we observe that "ESXi Host is violating CIS(v7 and above)" is missing from the alerts definition but we have v7 and above objects for Virtual Machine, vSphere Distributed Port Group, and vSphere Distributed Virtual Switch. This is the reason why the object breakdown section shows only these three entries: vSphere Distributed Port Group, Virtual Machine, vSphere Distributed Switch.
Manually import the alert definition attached with this KB article and then deactivate and re-activate the CIS management pack