I'm not sure how this interacts with open source principles. I think they are free to do whatever they want with their own website and indeed with open source tooling, but as a host for open source it could conceivably conflict with those principles.

A much debated aspect of open source is that it may be used for any purpose. The JSON licence sparked much of this debate.

More recently there has been suggestions for an ethical source movement, which advocate that source may only be used for ethical uses. I presume they must mean Good old christian, pro family, anti-terrorism, traditional values etc. the usual ten commandments stuff. Or perhaps they had something else in mind, it's unclear, but what ever it is that's the stuff that's allowed and the other stuff isn't.

I mean that's how I personally would define ethical. But anytime someone makes a claim like that, you have to ask "by what standard." And it's usually just "me."