The definition of a patent troll is hard. While your definition is currently the common definition, I believe we have to look how we reached that definition.

The first question we have to ask is: How do we not like patents to be used?

> its impact on the state of American aviation was indisputably negative.

We don't want patents to be used in a way that deters further research and advancements in that field.

Can we determine if a way of use will do that in the future? Unfortunately, as we can't see into the future, we don't know.

So we use the next best thing: We try to find patterns that strongly suggest that someone is abusing a patent.

And the pattern that we found is: People who just buy patents (sometimes for just $1) and don't produce their own are more likely to abuse patents. And that's how we came to today's definition.

But for the past, we can answer the second question. And we should use this as definition if possible.