I've experienced plenty of frustration, albeit outweighed by the massive benefits for my use case. And there are whole problem domains to which it's just not suited. I see these mentioned pretty frequently.
Rayon, the Rust library getting most of the discussion in this thread, is now 1.0: https://github.com/rayon-rs/rayon/blob/master/RELEASES.md .
Doesn't seem odd at all.
First, a lot of people commenting about Rust are enthusiastic recent adopters that haven't seen much of the language, including any real ugly sides yet.
Second, it's not entirely true, almost all Rust threads mention the steep learning curve, the slow compiler, and other issues such as the variadic generics (or lack thereof to be precise).
Third, we have seen the same "early adopter enthusiasts seeing it all rosy" circle for RoR, Go, Node, and Mongo, nothing out of the ordinary here.
You see the same with Rust, Elixir, VSCode, Elm, Purescript, ReasonML, etc.
It's not astroturfing, it's just a lot of beginners that are overly excited to proselytize their new discovery.