> Do those concepts actually cause difficulty for anyone other than compiler engineers, compared to not having them? I haven't personally seen, e.g., newbies st

> Do those concepts actually cause difficulty for anyone other than compiler engineers, compared to not having them? I haven't personally seen, e.g., newbies stumbling over them; Pretty much all of the features in the list are things that either I have struggled with when learning Rust (the Copy trait and lifetime elision), or I've seen beginner struggle understanding (both new hires, or students at the place when I gave Rust lectures).