Al Lutz had a very good update last year where he talked exactly about this E Ticket issue. WDI considers
The Little Mermaid: Ariel's Adventure coming to DCA an "E Ticket" in the truest sense of the word. It's a large attraction physically, has hyper themed environments with dozens of cutting edge animatronics and special effects, and immerses Guests in a wondrous, musical experience for nearly 10 minutes. All that equals E Ticket, just like it has in the past for Pirates, Haunted Mansion, Submarine Voyage, Small World, etc. But WDI is holding back from branding it an E Ticket publicly, because people will think it's a thrill ride not meant for little kids.
And WDI is smart with that. Todays audience, especially anyone who only knows about Disney from the post-1990 world, thinks an E Ticket has to have height requirements and elaborate restraint systems and massive G forces and twists and turns and drops in the dark.
When the Enchanted Tiki Room opened in 1963 it was the world's only
E+ Ticket. The Matterhorn and the Submarines were E Tickets for 75 cents in '63, but Walt's Tiki Room was so advanced and so expensive and so popular that you had to buy a separate ticket for it that was 85 cents. Later in the 1960's as the other ticket prices increased, the Tiki Room lowered itself to join the rest of the E Tickets in the park like Pirates of the Caribbean, Matterhorn Bobsleds, It's A Small World, etc.
An E Ticket means much more than G forces to Imagineers and longtime Disney fans. But to the young generation "E Ticket" only means short thrill rides and barf bags, if they even know what an E Ticket is to begin with.