> The use of Rc is already very widespread in projects when people don't want to deal with the borrow checker and only want to use the ML-like features of Rust

> The use of Rc is already very widespread in projects when people don't want to deal with the borrow checker and only want to use the ML-like features of Rust (Sum types, Option, Error etc.) And the fact that this hasn't caused alarm is kind of an issue. The problem with that is Reference Counting is WAY slower than good Garbage Collectors on modern CPUs. Reference Counting breaks locality, hammers caches and is every bit as non-deterministic as a garbage collector.