Thanks for your comment Lucio Maciel.
I would say Recommendation 2.3 and 2.4 supersede Recommendation 1.1, as you mentioned perhaps Proguard could remove it, or even if one day the Kotlin compiler (or maybe the decompiler) could be improve to not have that extra variable
Implicit parameter ‘it’ of enclosing lambda is shadowed is the use of
it that could be renamed to avoid ambiguity. For brevity I didn’t rename them.
Anyway, it is just recommendation, and there could be exception to them.