Since 1900, demand for refined copper increased from less than...

Since 1900, demand for refined copper increased from less than 500 thousand tonnes to over 20 million metric tonnes in 2012 as
demand over the period grew by a compound annual growth rate of 3.4% per year.

http://www.icsg.org/index.php/component/jdownloads/finish/170/1188

some interesting facts about copper production. If trends are anything to go by, then world demand will continue.

as for Goldman and Co, it's the oldest trick in the book to talk something down when you want to take a posititon.