You can do tons of stuff with purely safe Rust. The main things that you can't do are FFI, making self-referential structures, and dereferencing raw pointers.

And unsafe isn't a problem. It's a point of potential danger to be heavily audited, tested, and understood. Having the entire language unsafe by default is an obviously worse situation. This is throwing the baby out with the bathwater, like rallying against seat belts because you can still die while wearing one. An improvement is still an improvement. I don't understand why people criticizing Rust tend so heavily to let perfect be the enemy of good.