The entire US legal system is built on precedent; ruling the same way on similar cases ensures fairness and consistency. There has to be a significant reason to deviate from established precedent.

It comes from ancient English tradition even, when decisions were made by travelling magistrates. A respected magistrate could not willy-nilly settle disputes on his wisdom alone. He had to lean on previous decisions of what was considered reasonable and fair by the people, which created a consistent fabric of common law and culture over generations.

So the regressives upending another cultural tradition like this makes sense... and it's the right thing to do - from a revolutionary point of view. Something I'm not sure the Right totally understands yet is that if we ever get the chance at a real revolution, we'll need to overturn decades of court precedents as well to make it stick. You can't just put "our" judges in and think the system will heal over time. You have to recreate the system. It's sort of like killing the monarch's entire extended family when you depose him. You can't leave anybody alive that could reclaim the crown. The left understands that.