The correct answer to this open question is the following.
I think that although senators and representatives can create new laws without voter approval, constitutional voters must ratify amendments because an amendment is a serious thing that has to be wisely thought of without any bias or partisan preference.
Yes, Congressmen have the power to create laws. That is one of its powers granted by the United States Constitution. But to amend an article of the constitution is something very serious and that is why there is a complex process to do so. It takes time.
So difficult it is that in the history of the United States, only 27 amendments have been added to Constitution.
When the founding fathers drafted the new Constitution during the Constitutional Convention of Philadelphia, Pennsylvania in 1787, Federalists and Antifederalists debated and argued so much about this issue and decide to create a complicated process in order to amend the Constitution.