Earlier this year I was able to struggle-bus together my own bootable rust binary (and bootloader in assembly!) on QEMU in a couple of hours using his blog as a guide. It seems the LLMs have definitely scraped his blog, as if you go off the happy path they're absolutely useless in this endeavor, and few other resources on the topic exist.

You can have a look at this project that shows how with proper abstractions you can minimize unsafe Rust for low level firmware. Specifically look for page token, page allocator and page table implementations: https://github.com/IBM/ACE-RISCV

I went through it recently and I don't think there was anything in the blog that was out of date. There was mention in the blog of having to do some hacky things because certain features in rust didn't exist yet, but the hacky solutions provided still worked.