I find Rust's borrow checker too clunky for exploratory work. It breaks my flow and imposes higher cognitive load. The slow compiler doesn't help either.
That is fair. I have not done enough exploratory work in Rust to comment. Maybe there are abalysis patterns that can avoid bumping up against the borrow checker.
I tend to think the innately slow compiler is basically a fatal mistake. Rust will never be able to be used for large projects. It's not so obvious now because everything it's used for is tiny.
What supports that statement exactly? If you split your big projects into crates it would recompile pretty fast. C++ can also take ages to compile (eg. compiling Firefox from scratch). Keeping your code modular to get decent compile times seems like a win win.
I never compile C++ projects from scratch like I am forced to do with Rust.
The only code I compile from scratch in C++ is the code I write myself, everything else is available as binary libraries, something that cargo doesn't do, and it is not part of the near future roadmap, if ever.
Then, after compiled, most of the stuff lands on the VC++ metadata files, so incremental compilation and linking cuts even more time from the usual edit-compile-debug workflow.