The US doesn't have a minority rule death spiral because of social media, it has a minority rule cycle because the constitution literally entrenches minority rule via mechanisms like senatorial malapportionment, supermajorities, the electoral college and judicial review of policy (see citizens united, roe v wade, affirmative action) rather than merely procedure. It has experienced this before, sometimes devolving into outright civil war, without actually reaching death.

The technologies for resolving America's problems are well understood - majority decision making, parliamentarism, representation and participation of electoral minorities rather than inhibiting the work of the majority, a narrower scope of judicial review and/or a more flexible constitution. But as long as people say, as you do, "it isn't the thing that caused the problem that is the problem, it is some fancy gadget that is the problem", then you will be unable to solve the problems