Yes you are right!

Having an extra parameter on scalarmap is exactly equivalent to adding this parameter onto the front of the list you pass to reduce.

EG

  $z = scalarmap { $a * $b } 1, 2..10;
  # is the same as
  use List::Util;
  $z = reduce { $a * $b } 1, 2..10;
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All hail to perl's unfancy list flattening subroutine parameter passing!

This makes scalarmap completely redundant :-( It was fun inventing it though :-)