There is a known issues in VS for Mac 2022 and is currently under investigation. You can follow it on the Visual Studio Developer Community at error synchronizing changes from Xcode. The VS Developer Community is the official site for VS bug tracking.
What I did was to manually set the app icon folder with the correct json file and images then edited the .csproj file so that it reflexes the new custom icon names.
This is what I would recommend until a fix is available.
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