@Dan Meier-Conroy Thanks for posting in our Q&A.
Based on my understanding, all the app deployed by intune are listed under the "Applications" section of "Areas Managed by" even the app is uninstalled.
If you want to see the managed apps, it is suggested to click on "Create report" and check the export file(MDM Diagnostic Report). Under "Managed applications", we will only see the managed apps by intune.
I will share you some screen shots in my lab. The first app is uninstalled and it is still listed. However, this app is not listed under "Managed applications".
Hope it will help.
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