False positives of Lint/Void in assignments

Today I was working on autofixing rubocop offences and Lint/Void gave me a nasty surprise. Supposedly in Ruby the return value of assignment methods like def field=(value) will be special in that it's always the value passed, irrespective of what the last expression in the method body was. While true, this rule has an unusual exception - being called via super. In that case the last expression is returned, confusoring everyone.

Try this code and see:

class Parent
  def value=(v)
    @value = v
    :p # should never be returned, but using super in an inheriting class does get to it.
  end

  def value
    @value
  end
end

class Child < Parent
  def value=(v)
    parent_value = super
    parent_explicit_value = super(v)
    puts "Parent's value assignment returns #{parent_value}, whereas passing arg explicitly returns #{parent_explicit_value}"

    @value = v*10
    :c
  end
end

Child.new.value = 1
Parent's value assignment returns p, whereas passing arg explicitly returns p
#=> 1

Not sure what the takeaway here is. The cop is useful because it warns about code that will have no effect, but I guess it has a false positive case in assignment methods.