You've simply imagined this: "likely C# devs whose careers are aligned with the success of Microsoft". Once you frame it that way, it sounds terrible, but there's no evidence for it and the data I looked at doesn't support it. Your question "why do you allow it" has a similar framing. The answer is that we don't allow it.

The much more common case is that users don't want to see things that are clearly off topic for HN, such as teacup internet dramas. As I explained above, the overwhelming verdict of HN users is that there's nothing serious in this story. If they thought otherwise, it would certainly be on HN's front page. That's the flagging system working as intended.