After Effects' main window is not a real macOS window, which impacts accessibility apps.
I use the app AltTab, which simply lets you switch between open windows using a shortcut. The app is not able to properly detect the AE window because of this issue. Quote from my bug report to AltTab:
Then it means AE windows are not real windows. It's a bug on their side. You should open a ticket for them so they fix it. If it affects AltTab, it must affect other accessibility apps.
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To insist again: this is a bug on AE side. It should be reported. Screen readers and other apps are probably broken with AE.