No, the Supreme Court should not be able to block such a proposed amendment. After all, any amendment is, by its very definition, a change to the Constitution. That means that essentially any amendment to the Constitution would have to be unconstitutional. The amendment process is the way that we are given to officially change the Constitution. The Supreme Court should not be able to keep the people from changing the fundamental law of the land.
There are at least three cases in which amendments that were clearly against the Constitution as it was at the time were proposed and ratified. The first of these was the 13th Amendment, which banned slavery. Up until that time, slavery had been tacitly accepted by the Constitution in such places as the three-fifths compromise. Surely we would not have wanted the Supreme Court to block that amendment. Secondly, the 21st Amendment repealed Prohibition. It explicitly overruled a previous amendment that had enacted Prohibition. This would clearly have made it unconstitutional and yet we do not think it was a bad amendment to enact.
There needs to be a way for us to change the Constitution. If the Court blocks us from doing so, we have no way to change the fundamental law. This would be terribly undemocratic.