Can you give an example of what you mean by "complexity"? I think this could be an instance of people simply having different definitions.
Without a lot of experience (not to mention vast amounts of memorisation), everything is just hard and slow to get done. And I do mean by comparison with other languages I've used, from Objective-C to Java, from Typescript to Elixir (and many others).
Again, this isn't necessarily a complaint about the complexity per se. It might be necessary (I don't feel I know enough to judge), given Rust's uses and constraints. But the community consistently and obviously denies the difficulty. I think I understand the sources of the denial. But that doesn't make it any less irritating!
This is an answer on the forums to a fairly beginnery-looking question: https://users.rust-lang.org/t/what-does-borrow-mean/81794/3
In what language ecosystem other than Rust would that answer arise as an answer to a beginner's question? Haskell, or a research language perhaps. I can't make head or tail of the Rust Playground example there. In fact if I look through most of recent questions on the Rust forum, there's probably 1 in 10 where I even grok the question, let alone the answer. I haven't experienced this elsewhere. Rust has a culture of complexity, and its community is in a state of denial about it (for I think a fairly obvious reason). Furious denunciations ensue even if anyone dare suggest such a thing!
I do find the intense advocacy thing singularly odd with Rust. It's not like developers have to be convinced a thing is easy for them to use it. I'm still learning Rust (for reasons). But I don't feel the need to submit to social pressure from Rust advocates to feign ease.