I will agree the goalposts should not be moved. That said, the standards for what constitutes an "E" ticket level for new attractions have advanced over the decades; Technology and other innovations create far more (truly) immersive and epic-scale rides than could have been imagined thirty or more years ago. The Tiki Room was indeed an E-ticket, however, if you created a new "type" of the show today - using identical technology and presentation but centered around a different theme - it would not be an E-ticket in 2016 (could be impressive, though).
Nobody is comparing the Tiki Room with Expedition Everest. The two attractions were created decades apart; You cannot make a direct comparison without considering the variable of time.
The comparison is appropriate, though, in that you have expectations of a 2016 sports car that you don't have for a 1967 model (personal preferences aside). A newly built modern car with the horsepower and (lack of) standard features of a late 60's model would be laughed out of the mass marketplace; You didn't expect luxury features (navigation, comfortable seats, etc.) and maybe a 700-hp engine in cars back then, but you do today.
A car which was a fast sports coupe back then is still a fast sports coupe today, but it doesn't in any way equal modern cars nor should we expect it to meet such standards. Attractions work in a similar manner. The problem with ranking them (A-E tickets) is applying a 2016 standard to rank a decades old concept
Used within the context of some (many) Walt Disney World visitors, it is an apt description. Some people really seem to make it a hobby to go around and find things to be offended at, even when the term is more descriptive and not necessarily derogatory.
Were attraction rankings based on demand (they aren't), a very simple ride like Dumbo would have been the epitome of an "E" ticket attraction (it's not).