It was when it originally opened in the '60s and '70s, but considering that the ticket book system hasn't been in use for decades, technically nothing is classified as any type of ticket anymore. One can only speculate. If the ticket system were still around, it would almost certainly look a lot different than it used to. I'd imagine things like "it's a small world" would slide down the scale to a D-ticket with the advent of mega-attractions like the Tower of Terror and the Indiana Jones Adventure. Disney marketing might tout things like the Little Mermaid ride as their "latest E-ticket" but in reality if the ticket system were still around it would probably just be a C- or D-ticket. So, sure, in the context of the ticket system as it was in the '60s and '70s both of the Avatar rides would absolutely be classified as E-tickets, but in the modern day without any kind of guidelines for classification that have organically evolved over the intervening years, there's no telling.
Long story short, I think it's totally meaningless to try to classify any modern attractions with the old ticket system, unless it's a truly top-of-the-line, groundbreaking attraction like the Tower of Terror that would obviously be classified as an E-ticket.