Comment by warent

I'm pretty sure this is a result of non-technical people calling the shots on what roles they're hiring for.

  ROLE: Sr. Full Stack Engineer Level 5
  MUST HAVE:
  10+ YEARS JAVASCRIPT EXPERIENCE
  4+ YEARS JSON EXPERIENCE
  7+ YEARS PERL ON RAILS EXPERIENCE
  Linux
  Sketch / Adobe Photoshop / InVision
  PhD in Machine Learning

And not to soapbox here too much but but sadly I actually have come across a job ad demanding "4+ years JSON experience"