These protections were put in place to protect investors from creeping regulations that latin American govts might impose as a way of taxing. A shield, so to speak.
And of course, after NAFTA was passed, the investors converted that shield into a sword to attack US regulatory law.
According to the dems, it was a big conspiracy between Reagan and the Federalist Society. They, the dems, want to replace the investor protections with protections for labor, the environment, and social justice.
If nothing else, the dems are consistent.