I'm extremely productive in Rust vs other languages, especially for young projects where I spend a lot of time refactoring. Things like borrow checker errors just don't happen very often to me anymore, or they catch legitimate bugs and are generally quite easy to fix. I just don't run into them very often at this point.
I've written Python and Java professionally. In both cases I felt like I just couldn't express what I wanted to, at all times, in my program. This led to me being a lot less comfortable refactoring - relying on tests that were far too heavily tied to implementation details.
I had some really complex logic I needed to write for one of my services. Basically I needed to represent a 'thing' and that 'thing' could be in a few different states. I wrote out the code, types first, so that every state had a type. I was able to do this generically using Rust's associated types in a way that allowed me to implement the state machine for multiple 'things'. It was very testable, very readable code that I had high confidence in. I would have had a much harder time doing this in Java/ Python (I have done similar things, and you can get value from the approach, but not the same level). I've refactored that code a lot with confidence.
Speed is a nice bonus, but mostly secondary.