Oh no! A bad precedent. Wouldn’t want to have one of those. Surely precedent will protect us from having reproductive rights stolen, or declaring the president a king, or declaring the regulatory state invalid. The fascists are already on the march and have demonstrated they’re willing to trash precedent without the Democrats making the first move.
But none of that matters. Is this an existential issue or not? If it is, a constitutional crisis is warranted to solve it. You can’t say something is existential and then worry about not doing anything too extreme.
I read their point as being “because official acts are not defined and they’re the ultimate deciders, the Court can provide or withhold this immunity at will”. Turns out killing Republicans is not an official act and killing Democrats is.