"Safe" languages make it harder to write some classes of bugs; this is good. I wonder, though, whether it's not a better return on investment to focus on sandboxing wherever possible? I can run curl in firejail right now with no code changes whatsoever. On supported systems, pledge() and SELinux rules can mitigate attacks with minimal effort. And we get to keep existing programs without investing the man-years to rewrite something that works.