Even if Rust adds increasingly more "unsafe" features in order to appeal to new developer groups, I agree that it should remain a "100% safe by default language

Even if Rust adds increasingly more "unsafe" features in order to appeal to new developer groups, I agree that it should remain a "100% safe by default language", and they should continuously try to improve the performance of the safe code, rather than get lazy and say developers can just use the unsafe syntax if they want 3x the performance. This would only lead more and more developers to increase the usage of unsafe code. It would be even worse if Rust would allow unsafe code by default for any future feature.