I know that the focus of the “No Collaboration” rule was on private communications, but was that the intent of the rule to simply limit private communications? Or was it to truly prevent actual player collaboration through blocking the easiest means of collaboration?

If it’s the latter, then there might be room for two Special Case rules: No Private Communication and No Collaboration. To be honest, I’m not sure how much teeth a real “No Collaboration” rule could have.

The intention when it was proposed in 2021 was explicitly “to cut down on the power of cabals by forcing all discussions about the dynasty out into the open”.

An actual “players can’t work with or against any others in a multiplayer game” rule does seem a bit of a fool’s errand. A group could design a dynastic game that was entirely multiplayer solitaire, though, if they wanted.

don’t you have to include the tags when making changes to special case rules?

Mercifully not: “When referring to a Rule, the name used in reference to a specific Rule may be simplified by not including braces and any text between a pair of opening and closing braces, as long as such a reference would be unambiguous.”