A central tenet of originalism is that things which are not discussed in the constitution fall outside the realm of the court, and should be left for the people to decide in the legislature. This is a perfectly reasonable opinion, but it breaks down once you are required to cast a vote on an issue that you believe you should not be casting a vote on.

When faced with this situation, originalists on the court then vote for the status-quo outcome, effectively weighing in on an issue that they believe they have no business weighing in on. This is how originalist judges become conservative activist judges, even if they do not intend to "act."

Furthermore, to satisfy originalism's need for all non-enumerated issues to be handled by the legislature, it would require an unrealistic pace of drafting new ammendments to the constitution. In doing so, the seat of constitutional power would shift from the court to the congress, who would see little point in passing a law that might be considered unconstitutional when they could just pass an ammendment and hang the court out to dry. That is neither realistic nor desirable, but it is the sort of scenario that originalism seems to demand.

Lastly, originalism wasn't a philosophy the founding fathers intended for us to follow. Talk of a "living constitution" extends back to Thomas Jefferson. This is not to say that originalism is useless - of course not. But the founders never intended to craft a constitution with that had to be interpreted according to the realities of 1789. We know this because the constitution is silent on the subject of self-interpretation. The founders were lawyers and scholars, and were certainly aware that this ommission would work against originalist interpretation, which was their intention.