I think it's closer to "companies won't hire people to do $THING unless they've done $THING before." That, combined with overinflating requirements, interviews

I think it's closer to "companies won't hire people to do $THING unless they've done $THING before." That, combined with overinflating requirements, interviews that don't bear a lot of resemblance to the actual job, and interviews that are far more difficult than the actual job, plus perhaps a dose of what you said, seems to explain it. The first of these things is probably related to having people with HR or sales backgrounds (recruiters) reading resumes without understanding what they're reading. The latter two seems mostly like cargo culting FAANG interviews (and, from what I hear, even FAANG interviews are the same in the sense of not being all that related to the actual job yet also being more difficult).