I especially ran into it when doing last year's Advent of Code. I restricted myself to not using mutable state or custom data types, i.e. structs or classes, writing in a functional style. That style involved a lot of method chaining (i.e. x.map(...).reduce(...)...) and, of course, of closures.

I had to introduce a lot of helper variables to break up my longer transformation pipelines to make the compiler happy.

I hope Swift is not going the way of Scala any further, which I enjoyed a lot when I adopted it early on, but eventually turned into a monster of a language.

Btw., for recreational coding, I moved on to Elixir in the meanwhile.

Yeah, Swift is for creating end-user products, fast iteration, fast delivery. This is where it shines. For recreational coding definitely pick something that reflects your deeper aesthetic affinity, I totally get what you mean.