So, the site makes it easy to seek a binding decision against someone that's enforcable anywhere. If I'm the potential plaintiff that's great! But if I'm the potential defendant, I just say no to the request. I want it to be inconvenient to bring a binding decision. I at least make the P go through the pain of seeking out a physical arbitrator. In the status quo - no decision - I win.
You are right. Agreeing to use an arbitration service such as judge.me is much easier pre-dispute (arbitration clause) than post-dispute (submission to arbitrate, i.e. just case filing and hoping the responder accepts the case).