I agree. However, the reasoning behind that hard sell has less to do with actual technical considerations and more to do, I believe, with a combination of long held assumptions (not always right assumptions) about what Erlang is and the fact other other stacks have become entrenched and are good enough in the ways that are easiest to assess that Erlang/Elixir would be a tough sell. Add to that recruiting talent to work with Erlang/Elixir requires some outside the box thinking in HR hiring practices (something I rarely accuse HR departments of) and you have a tough sell.

This is all unfortunate. I do think the BEAM based stacks are underrated for applications outside of communications. Many of the same traits of resilience and resource utilization designed to facilitate communications systems actually apply to web apps and APIs, too. Elixir is very expressive and a good fit for writing business applications like accounting related software (what I'm currently working on). But... you have to think you can arbitrage those operational advantages into an overall competitive advantage... and that's a tough sell especially because it involves a lot of speculation which doesn't play out until you're getting to the end of a project.