Why does game mode not get triggered for my App?

I think I really have tried everything and I did all according to official documentation to support game mode on iOS or iPadOS but it doesn't matter what I do it just doesn't get triggered. Funny enough it works during development when I install it via Xcode but as soon as it is live on the store and when I install it from there game mode doesn't get triggered anymore. What I have atm

I have added (even though it is deprecated)

<key>GCSupportsGameMode</key>
<true/>

I have set the (but it seems only supported for macOS)

<key>LSApplicationCategoryType</key>
<string>public.app-category.games</string>

I have added

<key>LSSupportsGameMode</key>
<true/>

It just doesn't work. Is there anything else what needs to be done? Should the flag LSSupportsGameMode not be enough normally?

The reason why this is so annoying is that my app is a real time streaming app and I want to profit from minimised background activities for smoother gameplay and more consistent frame rates like mentioned in the documentation.