It is true for every job and skill, as well as for IT.
Only about a third of the IT jobs are in the tech industry. The best paying industries are not necessarily the ones that are hiring the most IT guys. The industries hiring the most IT guys may not want the latest and hottest skillsets.
This article shows where IT jobs are, and where the 5-year growth in jobs is projected to be for IT computer jobs.
The highest industries for growth will not be looking for the latest internet skills. Automotive and manufacturing will be looking for people working in established technologies. That is where this article says the new jobs will be.