There's a pretty consistent stream of relatively senior postings on the elixir forums[1] as well as a number of successful large-scale elixir deploys (Discord, Heroku, etc) that probably do their own recruiting. I get the sense that YCombinator's technical mentorship focuses on language silos they have experience in, so this community is probably just a bit outside the "sweet spot" for BEAM hiring.

Hiring juniors (and getting work AS a junior I imagine) is a challenge. I don't think Elixir is that hard to learn (and has fewer foot-guns than many competitors), but it makes evaluation more difficult.

[1] https://elixirforum.com/c/work/elixir-jobs/16