For the last 5-8 years there has been an ever increasing pressure on companies to "do more with less", "document operations" and "create procedures", i.e. to "streamline" all the "cost" centers of the organisation. IT is generally viewed as a "cost center" That is: costs money and does not create any output for the company.
This has led to a mindset where the whole of IT has been defined in terms of "projects" with inputs and outputs and companies want to "buy talent instead of careers" meaning that the company wants your work but not you as a person.
This has then led to companies running most things on "temporary staff" like consultants and contractors.
The effect this has had on IT is that knowledge about the infrastructure, systems, their quirks and how everything works together is not retained in the company and IT operations down to the little details are defined by non-IT people who think in terms of "procedures" "inputs" and "outputs".
So when you see something like "System administrator wanted, has to know XYZ operating system version 10,04 LTR, and the systems HPBS and VLSN" you can be sure that this requirement was written by a non-it person who thinks in terms of "inputs" to a problem.