This isn't meant to be an exhaustive list--it's just the domains I have experience with that Rust was a good fit for. Lest it seem like I'm saying Rust is a good fit for everything I've done, I also worked on Firefox where the UI was JavaScript, and I wouldn't hurry to rewrite that code in Rust. Nor would I want the throwaway stuff I write in Python or Ruby to be Rust.
Did you leave out a "not" here?
My guess was that since almost no one will pay more for a game's having fewer security vulns, there is less benefit to incurring the expense of Rust (takes longer to learn, development speed is slightly less)
That said, I don't really think Rust is a good choice for CRUD apps, because development velocity is more important than performance and they probably don't need to be multithreaded anyway.
But Rust would have been great for a lot of "systems" stuff that was historically written in Java, like Flink or Hadoop for example.
For example I like to play Civ with a friend, but stopped because about once every 30 minutes one of us would have their game crash. If it was written in Rust, I assume it might be more stable.
The point of Rust is to be a language that competes in the same niche as C++ but makes it much more difficult to write large classes of bug, much broader than just "security vulns".