Yes, themes are almost certainly working, but some plugins might not if they use functions not yet implemented. Sometimes there are also bugs in the compiler still, it's only in version 0.9.
There are plugins that can't be compiled yet, but otherwise no limitations, unless a plugin requires you to change the PHP source code while the site is live. This isn't allowed in wpdotnet due to security reasons.
Laravel is quite close to being run, Symfony should follow soon after. Mediawiki is already tested and runs.
Maybe it should be rephrased, but if you just want to setup WordPress on your server, the sources to WordPress and all plugins are still available in the original format somewhere, but they're not sitting on your server.
PeachPie doesn't allow this. We will enable the option once on-the-fly compilation will be implemented, but this is really really poor practice and we highly discourage the use of it.
Not disagreeing with you. Somebody posted the usecases below (https:/www.peachpie.io/usecases). The most common usecase is basically a legacy site in PHP that wants to/has to migrate to .NET. Reasons can include connecting PHP to .NET modules, performance enhancements, security issues that .NET doesn't have to worry about. There are other possible usecases though, like producing/consuming NuGets from PHP codes, distributing PHP apps sourcelessly, being able to run PHP apps on any platform or OS, extending massive PHP frameworks with C# modules, for instance. And then some funky exotic ones like crating games/apps/IoT software in PHP.
For most people (not saying it's your case) it's just a matter of not being that close minded and understanding that different companies or devs might have different language preferences. Or just to look outside their current box of thinking and see that any of the above might be useful for someone.
Depends if you mean this tool or the compiler in general. I'd recommend distancing yourself from your possible prejudices against either language, taking a step back and looking at it objectively. You won't be able to argue against the fact that a massive chunk of the internet is written in PHP. You'd also be hard pressed to disagree that .NET is an architecturally superior and highly robust language with a very good tooling and service ecosystem. You can make the connection.
Like someone below already answered, it's actually compiled to MSIL and what you're looking at is decompiled C#. All PHP functions have been reimplemented in .NET.