One part of the answer is rust's borrowing provided assurances that make it possible to clone less. The type system guarantees immutability in a lot of cases.

One part of the answer is rust's borrowing provided assurances that make it possible to clone less. The type system guarantees immutability in a lot of cases. For small scale examples this doesn't mean much, but larger software gains a few percents for free. This argument is cultural, not technical. I presume it is possible to write e.g. C++ classes with similar guarantees. But it is work you get for free in rust, so in practice it almost only happens there at scale.