It might, and if so you will switch but a very small minority of Linux users ever have the need to compile it themselves and out of that small minority only a s

It might, and if so you will switch but a very small minority of Linux users ever have the need to compile it themselves and out of that small minority only a small fraction will migrate to alternatives over this. I see Rust as a replacement for C long term. From this perspective it's absolutely ok to have a transition period (years in fact) where there are multiple toolchains used to build the kernel.