I write Rust and C++ for a living and completely agree with this. While I do like Rust in general, the language is so complicated that anything other than trivial programs is going to take way longer to implement than in any other language. Testing code in Rust is also half baked at best, I find that any other popular language has better capabilities than Rust in this aspect, including C++. I'd even go as far as saying that for a startup I'd use C++ before Rust if performance was a feature, otherwise I'd just go with something that has batteries included like Python or Golang.