Not true at all. Please listen to Farris. Then get back to me. A constitutional convention (article V) is NOT the “blank slate” you imagine it to be. It is for specifically enumerated, concretely designated AMENDMENTS to the consittution, nothing else.
Once a Constitutional Convention is called, any delegation can propose an amendment, and it then is sent to the states for ratification. There is no designated limits as to how long this Constitutional Convention would last, how many amendments could be proposed, nor how long states would be given to ratify amendments proposed.