It takes at most a week to get used to just about any syntax. It should absolutely never be a reason not to try a new language. That said, it would be lovely if Rust had a more ML-like, rather than C-like, syntax (being originally inspired by O’Caml), but that would likely not help attract devs in the intended target audience!
The insert function, for what it’s worth, has nonstandard formatting; the de facto standard rustfmt tool would use more newlines, making it clearer and less dense. The function also uses a couple of syntactic features like `if let`, which may seem unfamiliar at first but become second nature in a few days at most.
Every time a language developer chooses to give their new language a novel, let alone chaotic, syntax, they sin against the very premise of software development being an engineering profession. Can you imagine the madness if mechanical engineers had the same laissez-faire mentality towards the conventions and learned best practices of their field? Randomly chosen bolts to use left hand threads just because it suits their arbitrary whim, every thread has a unique pitch never seen before just to make the machine stand out from the crowd. Parts of the machine use hot rivets, not because the design demands it but because it scratches a retro aesthetic itch the designer had that day. Every time a new machine is designed it has a whole class of new never before seen quirky ways of being put together and any mechanic who pleads for standardization on common sense ways of putting a thing together are just told to git gud because the creative expression of the 'engineers' is paramount.
(This is how we end up with German cars, isn't it?)
It probably takes a week to get used to ugly pants too. OP's point is a matter of aesthetic judgement. I don't mind it either, but = |&I: can| -> Agree { Rust::Syntax }; is.a(Bit(&mut chaotic);