You're right it's not "absolute power" in one sense, but another sense it's kind of close. For example, they might not be able to pass a constitutional amendment, but they could still eliminate the law which sets the number of SCOTUS members at nine. Then, they could easily confirm as many Democrat-friendly justices as they wanted. In such a case, they might not need any constitutional amendments in order to do whatever they wanted, because they would control the Supreme Court, which interprets the Constitution. They would effectively have "absolute power", or something close to it.
Of course, this isn't just my imagination. Democrats have openly discussed packing the court. We are dangerously close to a one-party state, one which is increasingly totalitarian. Our only hope is that enough people wake up before it's too late.