Why use sourceCompatibility and targetCompatibility in modern Android development?

I'm experimenting with my build.gradle.kts file. It looks like sourceCompatibility and targetCompatibility don't affect anything when isCoreLibraryDesugaringEnabled = true. The code compiles and runs fine on both Android 5.1 and 13. Can I remove sourceCompatibility and targetCompatibility and forget about using them?

In modern Android development, the sourceCompatibility and targetCompatibility settings are used in the build.gradle file of an Android project specifies the Java language version compatibility.

• sourceCompatibility: This setting specifies the Java version compatibility for the source code of your project. It determines the version of the Java language features you can use in your code. It ensures that your code is compatible with the specified Java version and prevents the use of language features that are not supported by that version.

• targetCompatibility: This setting specifies the Java version compatibility for the bytecode generated by the Java compiler. It determines the version of the Java runtime environment (JRE) that your compiled code can run on. It allows you to specify a lower Java version than your source code's compatibility level, enabling backward compatibility with older JREs.

These settings help ensure your code works with the desired Java version, enabling the use of new features while maintaining compatibility with older Android devices and runtimes.

Starting with Android Gradle Plugin 7.0.0, the sourceCompatibility and targetCompatibility settings are not required in most cases. The plugin automatically determines the appropriate compatibility based on the Android Gradle Plugin version and the Android API level specified in your project configuration. However, you can still explicitly set these values if needed, for example, if you want to enforce compatibility with a specific Java version or if you encounter any compatibility issues.