Furthermore, "burner sim" implies an accompanying burner phone and all of the opsec that entails (eg only turn it on away from home), lest that "burner" number be trivially linked to your identity through databases that the telephone companies are happy to sell.

Moxie should know better, but this blog post repeatedly boasts about privacy while not addressing this at all. Getting basic encryption into the hands of the masses is a laudable goal. But when the popular threat model changes (eg pocket computer compromise incident to arrest at a protest - an "evil raid" attack), you either need to adapt or you've become an attractive nuisance.

Specifically I'm envisioning an attack where say ten protestors are arrested and found to have a shared contact, and then the police turn that phone number into a real world identity and go after that person for organizing.