The Glen Canyon Dam is an impressive bit of engineering but I can’t help thinking that J. W. Powell would be ashamed to have his name associated with the lake behind it. A big surprise for me was that the whole enterprise is operated by something called the “Bureau of Reclamation“. I kinda think “reclamation” would be taking the dam out.
The Compulsive Hiker 
I just spent a day there and could not disagree with you more! The lake is gorgeous — clean and uncluttered by buildings. It supplies water to a huge number of residents in the Southwest as well a producing electricity. You can rent a kayak in Page and paddle up to Antelope Canyon for an astounding day hike. Other adventures are also made easier by kayaking on the lake. The lake will be a mere blip in the geological history of the Colorado River Canyon. When we are all gone, nature will remove the dam and everything will be restored as you wish. Until then, people need to live –which requires water and electricity and even recreation.