And they're all inferior to what Elixir can do out of the box without ductaping on 3rd party tools. Running other services like Redis is not only not a breeze, it's an additional expenses and thing to monitor.
I assume most big Elixir apps use Redis or something similar anyway for its speed and reliability (it can periodcally persist for instance) instead of saving everything in memory. Redis is widely used with a huge community support and you usually don't want to lose all your background job info (you don't have to use an actual DB, but Redis seems like a good compromise for many companies). If you don't want Redis there are background job gems for Postgres/MySQL etc.
As for monitoring - in our current micro service world adding or removing Redis is peanuts. You have so much stuff to monitor you need strong monitoring, and usually a whole team dedicated to set it up. Doing that for Ruby or Elixir is negligble. I'd even say Ruby is more straightforward to monitor for devops people than Elixir (that's from stories I've read, not an expert on that).
There's plenty of real issues with Ruby (and with Elixir), but what you're arguing here is simply non issues imo.
Fair points regarding eventually using redis; it is common. But we haven't had to reach for it yet and handle some light caching and background jobs right in Elixir.
As for monitoring, it's better than it used to be - Elixir's Telemetry library is pretty awesome. There's even some UIs built for it:
There's plenty of real issues with Ruby (and with Elixir), but what you're arguing here is simply non issues imo.