I would love to be able to put the C# debugger into interpreter mode and be able to change anything, anywhere while debugging and keep on trucking without having to stop debugger, make changes, restart debugger, etc..
I think any hot-reloading solution for a big, complex, introspective/reflective language is going to have some warts* and places where it stops working in some scenarios. The trick is just to minimize those to where they don't get on your nerves on a daily basis. C# will hopefully get there soon.
* Unless, that is the language is designed from the ground up to support code reloading. Erlang/Elixir's runtime inspection/injection/behavior alteration capability is second to none, and largely replaces the role of a true/traditional debugger. And you can do other cool stuff with it like zero-downtime in-place deployments, though that doesn't exactly come for free.
> ... uses the new Mono IL interpreter to run managed code at runtime... to be used for quickly reloading C# code and prototyping
So maybe it will/can provide the foundation for faster edit cycles with native apps and not just WASM.