If a company provides products/services to someone with the knowledge those products/services will be used for a crime...then yes.
For example it’s legal for an arms dealer to sell a gun, but illegal to sell a gun if the seller knows the gun is being purchased with the intent of being used in a crime.
Here what you have is Salesforce who allegedly sold its products/services to backpage knowing their software would specifically be used to facilitate prostitution and human trafficking. Whereas you - for whatever reasons - seem to be concluding salesforce had no way of knowing their products/services would be used by backpage in the commission of a crime (ie your Windows analogy). However, the facts suggest SalesForce was well aware of backpages business practices and activities (and was publicly fighting against the same criminal activity, while simultaneously supplying software that facilitated the same). It’s a tough case but human slaves and a corporation privately profiting from these activities while publicly “fighting” against the same won’t play well to a jury.