> C#.NET is a compiled lamguage and doesn't need to be interpreted at runtime.

That's not a great summary. .Net is complex. There's AOT compilation but not available for all purposes. There's JIT which applies most of the time to C# code compiled into msil. From there different things can happen depending on implementation, which may also include running the code via an IL interpreter.

Doesn't just Mono have an interpreter (which is now being added as part of tiered compilation)? Aside from .NET Micro. I was under the impression that .NET by and large was JIT-only. Yes, by now it's more complex, and there have been multiple different implementations, few of which would be relevant on a Windows Server environment for ASP.NET. But AFAIK a situation like in Java where the official implementation has an interpreter and a JIT (and debugging usually falls back to interpreting with horrible performance) has never been the case in .NET.

last time I checked, AOT is heavily used, and if you load your assemblies into GAC you're getting AOT compilation for pretty much all code if you're not going to generate bytecode at runtime.