This is all great thinking. Except for those of us who live in a world where most of their OS and utilities and libraries were originally written decades befor

This is all great thinking. Except for those of us who live in a world where most of their OS and utilities and libraries were originally written decades before Rust existed, and often even before Java existed. And where "legacy" C code pretty much underpins everything running on the public internet and which you need to connect to. There's a very real risk that reimplementing every piece of code on a modern internet connected server in exciting new "safe" languages and libc-type things - by a bunch of "modern" programmers who do not have the learning experience of decades worth of mistakes - will end up with not just new implementation of old and fixed bugs and security problems, but also with new implementations that are incompatible in strange and hard to debug ways with every existing piece of software that uses SSH protocols as they are deployed in the field. I, for one, and not going to install and put into production version 1.0 of some new OpenSSH replacement written in Rust out Go or Java, which has a non zero chance of strange edge case bugs that are different when connecting to SSH on different Linux/BSD/Windows distros or versions, across different cpu architectures, and probably have subtly different bugs when connecting to different cloud hyperscalers.