@WVD ISSUE Apologies for the delay in response and all the inconvenience caused because of the issue.
The Windows Virtual Desktop app is for the management of the service, and includes granting permission for the service to call your Azure AD for user validation, service principal validation, etc. The Windows Virtual Desktop client app is for the end-user login, where you can control MFA/Conditional Access policies.
Now in classic deployment model you had to apply conditional access on both component separately whereas in new ARM model you can directly apply it on WVD app and it will be applicable on both. Since Remote Desktop client is used for Windows Desktop to access Windows apps and desktops remotely from a different Windows device Conditional Access policy is applied on it.
You can refer to this Conditional Access Policy with WVD example as well for more information.
Hope it helps!!!
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