It means that the extension in androidx is not needed anymore.
Simply remove its import import androidx.lifecycle.observe.
It will be actually deprecated in androidx. Read more reasoning there.
EDIT:
Please note the “issue” from Erik Hoogendoorn
This change causes values from the observed LiveData object to be interpreted as nullable(since the converted lambda syntax is based on nullable Java code). This was not the case for the Kotlin extension and causes a loss in functionality for the user. In my opinion this change should be reverted and a different solution found.
I’m curious if they will rename & retain the helper or come up with another solution.