Most of the stuff is something that looks esoteric to someone who was taught C or Fortran or who taught him/her-self VB and is so used to imperative programming, that he/she cannot think outside that old tiny box. The people that find references hard and higher order functions rocket science.

And the DATA filehandle is no more esoteric than a print statement. A bit unusual maybe, non-obvious probably, but esoteric? That's a very big stretch of the meaning of the word.