Given the common retort for why not try X project in Y new language is "it's barely used in other things. Let's wait and see it get industry adoption before trying it out" it's hard to see it as anything OTHER than a zero-sum game. As much as I like Rust I recognize some things like SQLite are better off in C. But the reason you see so much push for some new languages is because if they don't get and maintain regualr adoption, they will die off.