I agree. For most CRUD applications, developers should mostly integrating off-the-shelf components, and not constantly be reinventing the wheel. The reason for that being, that customer value (and satisfaction) can be attained by delivering a usable product, and that is what pays the bills at the end of the day. Whether that product is implemented in Python or Elixir is often not visible.

On the other hand, if the task at hand requires a novel approach and using tools that are less frequently used, then that will also be justifiable. Are you developing something that only makes sense to run on the BEAM virtual machine? Go ahead and work with Erlang or Elixir.

Now a third category is programming for enjoyment. In that case you don't work with the constraints of profitability, and you can just have fun. And don't worry too much about Beating the Averages (http://www.paulgraham.com/avg.html)