By analogy - name a great business impeded by corruption in the government. Unm. We know there are great businesses in America and not that many in (more) corrupt countries, but we can't point at killed businesses themselves.
I can name you a great business from one country that was impeded by corruption (or at least a connection to industry that should not have existed) in the government of another though:
But the magnitude can only be determined by having lots of examples. You are saying that there is no point in collecting any examples at all but when you don't have any then the magnitude could still be '0'.
By showing examples, preferably lots of them the magnitude will get at least a lower bound.
I'm not sure it's possible for people to imagine a different world that easily. The differences caused by software patents not existing are pervasive and cumulative. Like the surprising effects of compound interest, I think a world without the 20 years of software patents would be in many ways unpredictable or even inconceivable for those of us who lived through this reality.
The original question may make sense in a limited fashion, but it frames things poorly as it's asking for specific incidents to illustrate a systemic effect.
