As long as companies keep expecting experience in very specific technologies (only at work—400 hours on a hobby codebase don't count for as much as 40 hours writing something at a job for determining competence in a language or framework or whatever, it seems) this will keep happening. It's really, really dumb, but there's little other choice for folks who want to keep their skills (=the names of tools & languages they've used to write something for pay) up to date (=trendy high-paying buzzword compliant).

Doubly true if you're not all-in on one of the major Bigcorp silos (Java, C#).