> disallowing anything that might be a potential thread safety issue will give you a pretty limited language.

Safe Rust doesn't seem that limited to me.

I don't think any of the C# work I do wouldn't be possible in Rust, if we disregard the fact that the rest of the team don't know Rust.

Most of the programs you eliminate when you have these "onerous" requirements like memory safety are nonsense, they either sometimes didn't work or had weird bugs that would be difficult to understand and fix - sometimes they also had scary security implications like remote code execution. We're better off without them IMNSHO.