> To prove a point, I spent an hour reading his opensource project
  > and found several resource leaks

Sounds like some interesting case studies. Could you share some?

  > > if I find [… typo words(?) omitted … ] a leak in the code I
  > > usually refactor to make the correctness more obvious.

I should rewrite this as - if I find a leak that I accidentally introduced, I will refactor in the process of correcting it, to make the mistake harder to repeat and the correctness easier to confirm.

There are non-language mechanisms that help code run safely, like Wasm, which is a sandbox. Also msan and asan should be used more.

Thinking that changing the language is the right way to fix all the problems you mentioned still seems like a premature assumption. The fact that 100% perfection is worth pursuing at all costs is theoretical and you could be losing things more valuable in the process - e.g. FFI bindings suck, and the added fragmentation in having so many languages in the craft is a pernicious cost with a multitude of aspects to it.