Why not generate config/releases.exs and use "import Config" by mix phx.new automatically?

Based on doc https://hexdocs.pm/phoenix/releases.html#releases-assemble
User need to these to create release config.
My question is why not just generate these by default. So there is no need to do these steps manually.

  1. Rename config/prod.secret.exs to config/releases.exs
  2. Change use Mix.Config inside the new config/releases.exs file to import Config (if you want, you can replace all uses of use Mix.Config by import Config , as the latter replaces the former)
  3. Change config/prod.exs to no longer call import_config "prod.secret.exs" at the bottom

The phoenix generators for v1.5 support elixir versions back to 1.7. Releases and Config are a elixir 1.9 feature.