[gridspy]

To build on your argument:

The 20% decent shops are retaining their engineers and only growing at a sustainable rate. Available new jobs are filled with a referral since every employee is constantly bragging to their friends. So they post few / no new jobs online.

The 80% crappy shops are shedding employees (turnover) and also poorly managed so they fire everyone and rehire later. Only the worst employees decide to remain during such a purge. So most new posted jobs (more than 80%) are for such companies.

Then the 80% crappy companies talk about their issues finding staff and you get articles complaining how hard it is to find XYZ employees (interns, C++, even supermarket staff). But the real problem is the company in question, not the industry as a whole.