Generally though, the issue is mentioned in a broader context than just "someone did a bad thing with the internet", and more that the community behind Bitcoin, and the libertarian philosophies which guide it, give rise to the scams and dark market uses of the currency.

When evaluating and discussing any technology, you're absolutely right: it is unfair to criticize it based on a few bad examples.

However, it is fair to look at a technology and consider whether the "legal" outweigh the "illegal" ones, and if not, why.

The author makes this point succinctly.

I think the bigger picture here is that there is a serious worry that bitcoin will benefit those who participate in illegal activities far more than those who do not -- that it offers an advantage that most legal activities don't require or value heavily.

I must give you credit, this is very well said. This is a legitimate concern. I feel as though this is what others have been attempting to say when using the "illegal activities" argument.