the text editors/ides I use today have bracket matching and with eslint it's been easier to track missing/extra bracket bugs, the example you have is heavily exaggerated, nesting like that is bad code with or without brackets
So is having to set up preprocessors whenever you want to use Coffeescript. Which is easy in Rails but a challenge in many other scenarios such as simple static sites.
Not to mention the number of projects I've joined which has a random mix of both .js and .coffee files.
I'd prefer spacing over bracket if it was natively supported in the language as it is in my favourite languages Erlang, Elixir, and Haskell. But that's not the case here.