Only in the case where the government is compromised by, say, regulatory capture [1].

[1] https://en.wikipedia.org/wiki/Regulatory_capture

What about cases in which the government is compromised by incompetence and/or poor ethics, esp. due to ignorance?

As someone who works in government, you're dead right about incompetence, and I would add 'ignorance'. These are the two things I have seen do the most harm, by an extremely large margin. And I think it's inexcusable.

I'd argue the same thing for corporations as I would for governments: we shouldn't tolerate individuals, occupying some powerful position, who harm others due to their own 'ethical carelessness'. In fact, that seems like a reasonable standard to apply to individuals, full stop. Individuals should be held accountable for their actions; we shouldn't shunt the blame to some incorporeal concept (i.e. 'governments', 'corporations').

At least on the surface that's an extremely fascinating idea. I guess I would want to understand why we created institutional protections for individuals in the first place before forming any opinion about whether removing such protections is a good idea.

You have to ignore reams of political science to believe that claim.

I think "institution" is the word you are looking for.