
In case it helps, this is what I got when I ran EtreCheck (paired down to protect some privacy):
Before you install Acrobat Reader DC on your computer, ensure that your computer meets the minimum system requirements. If you're on macOS Big Sur, read the Big Sur compatibility document to understand the know issues. Within a few seconds of me opening Acrobat Reader DC, the rainbow wheel comes up and the application hangs. Application is 'not responding' and I have to force quit. I cannot use the application at all. I've tried trashing the application (there appears to be no way to uninstall), deleting the trash and downloading and reinstalling.
Adobe Acrobat Reader Dc For Mac Not Responding Can 27t Force Quit Responding
Launch Agents:ⓘ

[not loaded] com.adobe.AAM.Updater-1.0.plist (2015-12-28) [Support]
[failed] com.adobe.ARMDCHelper.cc24aef4a1b90ed56a...plist (2016-02-02) [Support]
[loaded] com.adobe.CS5ServiceManager.plist (2012-02-12) [Support]
Adobe Acrobat Reader Dc For Mac Not Responding Can 27t Force Quit Working
[loaded] com.oracle.java.Java-Updater.plist (2013-01-01) [Support]
Launch Daemons:ⓘ
[loaded] com.adobe.ARMDC.Communicator.plist (2016-02-02) [Support]
[loaded] com.adobe.ARMDC.SMJobBlessHelper.plist (2016-02-02) [Support]
[loaded] com.adobe.SwitchBoard.plist (2012-02-12) [Support]
[failed] com.adobe.fpsaud.plist (2016-04-15) [Support]
[loaded] com.barebones.authd.plist (2012-04-30) [Support]
[loaded] com.malwarebytes.MBAMHelperTool.plist (2015-12-13) [Support]
[loaded] com.microsoft.office.licensing.helper.plist (2010-08-25) [Support]
[loaded] com.oracle.java.Helper-Tool.plist (2013-01-01) [Support]

User Launch Agents:ⓘ
[loaded] com.adobe.AAM.Updater-1.0.plist (2012-02-19) [Support]
[failed] com.adobe.ARM.[...].plist (2012-03-10) [Support]
[running] com.akamai.single-user-client.plist (2015-09-25) [Support]
[loaded] com.google.keystone.agent.plist (2016-03-03) [Support]
User Login Items:ⓘ
(...)

Adobe Acrobat Reader Dc For Mac Not Responding Can 27t Force Quit Drinking Alcohol
Other Apps:ⓘ
[running] com.adobe.PDApp.AAMUpdatesNotifier.155552.BBF964E7-A2C2-4E67-B1E4-E4F1C4630641
Adobe Acrobat Reader Dc For Mac Not Responding Can 27t Force Quit Claim
[loaded] com.adobe.Reader.49632
(...)
[loaded] 396 Apple tasks
[running] 184 Apple tasks
[killed] 19 Apple tasks
Internet Plug-ins:ⓘ
FlashPlayer-10.6: 21.0.0.226 - SDK 10.6 (2016-04-22) [Support]
QuickTime Plugin: 7.7.3 (2016-01-29)
AdobePDFViewerNPAPI: 15.010.20060 - SDK 10.8 (2016-03-08) [Support]
AdobePDFViewer: 15.010.20060 - SDK 10.8 (2016-03-08) [Support]
Flash Player: 21.0.0.226 - SDK 10.6 (2016-04-22) [Support]
Default Browser: 601 - SDK 10.11 (2016-01-29)
(...)
May 6, 2016 4:36 AM