I meant he could have said: "Because I love Rust, I'm giving this for free to be used in Rust codebases", instead of "this would never exist if not for Rust".
Or maybe he's serious, maybe the Rust ecosystem literally saved him from death or something like that.
Ah, got it! You were being literal and he was not. That's where the confusion is coming from. Your comment came across as mildly aggressive which is probably why you're getting downvoted, but you were just pointing out that what he said made no sense in literal terms which is true.
I don't think it was intended to be interpreted literally. The intent and the feeling behind what he was communicating was represented clearly.
The saying is perfectly standard and meaning has been granted equivalence to your alternative, through common usage. It’s really not a point worth making, or arguing.
Alternatively you could read it as “I wouldn’t have bothered doing this if rust wasn’t there.”
Or maybe he's serious, maybe the Rust ecosystem literally saved him from death or something like that.