That's the reason for Mara's Mutex. I know, it doesn't seem like five minutes, but Mara's is now the previous version of the Rust Mutex implementation.
std::sync::Mutex::new became const in 1.63, which was over two years ago.
Sorry, maybe I was unclear, when I pointed out that this work was in 2022 that's not because I was trying to say it's recent, that's two years ago. The current work was in 2024.
Edited to add: Since we're going back and forth I read the blame log, the Linux implementation, with which I'm most familiar, is still 85% Mara's although with some meaningful changes from 2024.
std::sync::Mutex::new became const in 1.63, which was over two years ago.