what is the significance of iOSApp flag in installApplication command?

Without iosApp flag in the InstallApplication command we are able to install an iOS app in mac11 device.
   https://developer.apple.com/documentation/devicemanagement/installapplicationcommand/command
               As per doc, this flag has to be set to true so that ios app can be installed on mac device, but even without this flag ( default false), the iOS apps installation on MacOS 11 is successful.

What is the significance of iOSApp flag?
what is the significance of iOSApp flag in installApplication command?
 
 
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