> worlds apart beyond the superficial syntax similarities

I never understood this argument. That "superficial" syntax is what I have to stare at, reading and writing, for 8 hours a day. That I actually enjoy doing so is therefore hugely important to me.

I mean, you can make the same argument against Elixir itself, and I've seen it done - Erlang old-timers arguing against the necessity of these "superficial" syntax improvements. Suffice to say that I profoundly disagree.

I didn't say the syntax is superficial - I'm an Elixir fan, in fact. I meant the similarities with Ruby syntax are superficial.

Ruby does lend itself to writing a lot of functional code. One can write Ruby so that it looks very similar to Bash or other Algol-derivatives, but it's also possible to write code which avoids side effects, mutable state, or variables in general.

Genuine immutability, ie. the deep copy variant, isn't that easy to work with in Ruby. At least not without a significant performance hit and who wants to add a performance hit on top of Ruby's baseline performance?