They probably work a bit faster than the originals

There are some commands doing string processing that have been rewritten to use SIMD instructions which makes them inherently faster. On the other hand there are other commands where they're performing worse than GNU coreutils: https://www.phoronix.com/news/Ubuntu-Rust-Coreutils-Perf

Over time they will probably close the performance gap for those outliers, but if the GNU coreutils maintainers wanted to accelerate the same commands with SIMD instructions they could also do that. There's no real reason why long-term one should be faster than the other, except for whichever project gets more attention from maintainers.