This seems unrelated to the topic at hand, which is whether Rust results in a net improvement in the time required to deliver (systems) software that meets a particular set of requirements and those requirements include resilience to handling untrusted inputs.
Of course adding an additional set of tooling complicates an environment. I'm sure that was the case for Google in adding Rust to Android as well. And yet - it seems to have proved worth it. And I suspect that in the long term it will prove likewise for Linux, because Linux shares the same requirements and has a similar threat model it needs to guard against.
"This seems unrelated to the topic at hand, which is whether Rust results in a net improvement in the time required to deliver (systems) software"
A lot of your argument assumes that you've already have an entire working build environment readily available. If this is not the case, what used to be a fairly straightforward C compile now becomes an massive ordeal
Of course adding an additional set of tooling complicates an environment. I'm sure that was the case for Google in adding Rust to Android as well. And yet - it seems to have proved worth it. And I suspect that in the long term it will prove likewise for Linux, because Linux shares the same requirements and has a similar threat model it needs to guard against.