alt Hacker Newsthey also need the means to block interactions with that foreign party so their own rights aren't potentially stomped
Yes. That's the point. If you choose to do business with someone you also accept the jurisdiction of their local courts and laws. If you don't want that risk then do business locally.
This exposure however isn't limited just to 'business'. When you make comments online or publish open source code you're also potentially exposing yourself to other jurisdictions and their laws.