Rust heads into the kernel?

So in essence you're arguing that it'd better to have every C driver implement their own versions of kmalloc, printk, etc. because that'd only make 5% of the drivers vulnerable to certain bugs instead of 100% of them if those functions were to have issues?

To answer your question, yes, it's a lot better to have 100% of the Rust drivers vulnerable because they all use the same function if that means that 100% of the drivers are simultaneously fixed when an issue is remedied in the common library, rather than having each driver have its own implementation.

I know there are people who think static linking and bundling is a good idea, but I certainly don't belong to that camp.