Sit me down in front of Visual Studio and I can write code just fine. It's just I do so while consciously thinking about the editor and how I'm using it more than I would in my preferred vim environment, where things are largely subconscious through familiarity.
We had a little feature idea to include a screensharing mechanism so developers can use their ide. But sadly, only chrome supports that feature as of yet. We would probably add it later.
I assume that you mean WebRTC, and we have had it for a long time. Some bits are deactivated by default, but you can activate it with preferences if you need. I assume that any interviewee can be expected to reach into their prefs.