From what I've seen it encourages writing highly dynamic code that is extremely difficult to follow if you didn't write it. This is based on me trying to understand Gitlab's code. I have tried to read it to understand several different features and behaviours and every time I always get to a bit of code where I can't find the caller or callee.

Compare to VSCode which is a similarly huge codebase that I have contributed some small fixes and features to. It's night and day. Just click things to follow them. The only time it is even slightly difficult is when there's an abstract interface and then it can be a little tricky to find the concrete code that you want. But still very doable.

I think you'd have to be crazy to pick Ruby for anything other than tiny one man shows.