One of many problems with that theory - the ocean would first have to rise to put extra weight on the bottom. As I u understand it, ocean levels haven’t changed much, maybe a fraction of an inch? That small amount of extra weight is insignificant compared to the weight of a column of water thousands of feet high. How stupid do these guys think we are?
Obviously, stupider than them. Since they are as stupid as a pound of rocks, they must think we are as stupid as a pound of feathers.
Even if the supposedly melting glaciers added 20 ft to the worldwide sea level, that is a minuscule amount of water in comparison to the average depth of the oceans of over 2 miles. It is adding roughly 0.2% to the weight of the ocean. Big deal!
As to how stupid they think we are, they are measuring all of society by those people who actually believe them. So, the answer is that they believe us to be infinitely stupid. Fortunately, even my dog is smarter than everyone who believes in global warming, and to illustrate her level of intelligence, she is constantly sniffing the rear ends of other dogs.