The reason that there's not much of a line, I think, has to do with how quickly this ride loads. However, I agree that the queue area is ridiculously long for no apparent reason. I do like the queue though. It makes me feel like I am going underwater. I think the ride is pretty cute too but there seems to be a lot of people like you who don't like it.
I agree, the "Omnimover" rides like Nemo have amazing capacity!
And it depends on what time of the day you ride, too. Between around 11 AM and early afternoon, when crowds in Future World are at their peak, I've seen the Nemo waits go over 30 minutes, with the queue line spilling outside the building and winding back and forth! I've seen this happen on extremely crowded days, but also on some medium attendance days as well. Yet in the evenings on those same days, or early in the mornings, you can usually walk right on.
I like the queue, also! To me, it has good storytelling in the way you gradually go under water. People complain about the missing hydrolators, and I think the queue addresses the idea of how you get underwater. And I love the fishies that form various shapes, like in the movie!
And of course, being an animal lover and Finding Nemo fan, The Seas is my favorite pavillion at Epcot, and the ride is my second favorite Epcot ride, behind only Figment. I love its cuteness, warmth, humor, and catchy "Big Blue World" song!
I liked the pavillion before it had Nemo, and LOVE it even more now!
PS. French Quarter - being from New Orleans, I like your avatar!