> Anecdotal evidence, but I saw someone a few months ago who had an active Clojure blog, gave talks on Clojure, contributed to multiple interesting projects on GitHub, but was unable to find a job before literally running out of money and going homeless

That's a bit hard to believe.

Surely someone in this situation would settle with taking a job programming in a different language instead of going homeless?

It's also possible they placed unreasonable demands (I notice a lot of people looking for jobs in niche languages often ask to work 100% remotely too).

If you work in a niche language, you need to be ready to compromise in certain areas, such as having to relocate.