We don't have enough parallel universes to allow all uses of all junction types - in the absence of quantum computing the combinatorics are not in our favor.
But the possibility of abuse may be a good reason for leaving capabilities out of other computer languages, it's not a good reason for leaving capabilities out of Perl.
The random quantum fluctuations of my brain are historical accidents that happen to have decided that the concepts of dynamic scoping and lexical scoping are orthogonal and should remain that way.