A good lawyer would probably say something like "it depends".
It's entirely possible for a copyright owner to construe some kind of secondary liability based on your conduct, even if the underlying software is legal. This is how they ultimately got Grokster, for example - even if the software was legal, advertising it's use for copyright infringement makes you liable for the infringement. I could also see someone alledging contributory liability for, say, implementing features of the software that have no non-infringing uses. Even if that turned out to ultimately not be illegal, that would be at the end of a long, expensive, and fruitless legal defense that would drain your finances.
It's entirely possible for a copyright owner to construe some kind of secondary liability based on your conduct, even if the underlying software is legal. This is how they ultimately got Grokster, for example - even if the software was legal, advertising it's use for copyright infringement makes you liable for the infringement. I could also see someone alledging contributory liability for, say, implementing features of the software that have no non-infringing uses. Even if that turned out to ultimately not be illegal, that would be at the end of a long, expensive, and fruitless legal defense that would drain your finances.
In other words, "chilling effects dominate".