It's easy to make a crotchety list of over-rated things, but also important to remember that one man's meat is another's poison. I have no argument with some of the items on the list, but I'd like to speak in defense of some, too.
To dismiss Las Vegas as a theme park is to miss the point. It IS an adult theme park, and its wonderful tacky self is why I like it. That and the fact that it's a cheap landing point for Death Valley and the Grand Canyon/Boulder Dam.
Never been to Loch Ness, but the beautiful and quiet air of the picture in the list lead me to think I'd like to take a day there sometime, hopefully undisturbed by aquatic monsters.
Prague is another case in point. Certainly many other cities in Europe have beautiful and unique old architecture...note the word 'unique' because similarity and difference is part of what keeps me on the road. In Prague's case, there is also the old Jewish cemetery and related buildings which are a thicker survival than nearly anywhere else.
What would I add to the list—my own crotchets? Definitely Orlando. I've no interest in the assortment of theme parks there. I've been to professional conferences there, and found the area lacking in walkability, reasonable non-chain eating options and general tone. But I also have to admit that my feelings keep me from returning to see if perhaps I have under-rated it!