Inventory Installed Antivirus & Antispyware
In order to populate the AntiVirus & AntiSpyware page you must extend hardware inventory to include the AntiSpywareProduct and AntiVirusProduct WMI classes from the root\securitycenter2 namespace from a Windows 10 computer . Skipping this step will not generate any errors however, the "Antivirus & Antispyware" page will not populate. The Antivirus & Antispyware page reports on both third-party and Microsoft Defender installation and activation status.
For more information on extending Configuration Manager hardware inventory see the section Add a new inventory class on the How to extend hardware inventory in Configuration Manager documentation page.