https://dnd4.fandom.com/wiki/Rule_0Rule 0 or rule zero in tabletop role-playing gaming is the unwritten but commonly understood rule that the game master can override published game rules for any reason.
There. :P
Rule, that enables any Wizard to cast Cleric spells ... if GM (Larian) say so. :P.
I mean, if it's unwritten (and from a fandom site) then it's not necessarily an actually a rule of the system, but instead homebrew. Though yes, something close to rule zero is written in the DMG pg 4, saying that "the rules aren't in charge; the DM is."
But this just brings us back to the questions: "Why change a rule? Are the implications of this change thought out? Does it make the game better or worse?" Yes, Larian has the right to change rules as they are the DM. But that doesn't mean their decisions are inherently good - e.g., see cantrip surfaces and Advantage High Ground/Backstab, things which saw huge player outcry and were subsequently fixed by Larian.
And as always, relying on players to self-police their actions in-game is not good game design. We should be playing against the game, not against ourselves.
