Phoenix / Elixir (really, BEAM) enforce a worldview that results in non-bottlenecking code. You can do this yourself with a certain amount of disclipine in other languages. You should do this yourself if you are getting millions (or billions, etc...) of hits per second to gain access to system with a lower constant than BEAM. This is why Discord (for example) shifted to Rust.
Two interesting things are true:
1. Engineers have through lack of experience (or care) bottlenecked systems that had 12 views per day. Guardrails are useful particularly if there are shared resources or bottlenecks can impact busier neighbors.
2. The threshold where a shift out of Elixir is a good idea climbs at the same rate as Moore's law. Discord made their Elixir->Rust moves a lot later than Twitter made Ruby->Java ones.
Two interesting things are true:
1. Engineers have through lack of experience (or care) bottlenecked systems that had 12 views per day. Guardrails are useful particularly if there are shared resources or bottlenecks can impact busier neighbors.
2. The threshold where a shift out of Elixir is a good idea climbs at the same rate as Moore's law. Discord made their Elixir->Rust moves a lot later than Twitter made Ruby->Java ones.