Doesn't matter if you understand it or not, these things are still true. It is a fact that it's one of the few attractions at the park that relies entirely on physical sets/effects. It does take people off the street and give them an attraction with a low wait time. And if a poster says that the visitors he took liked it more than Transformers, that is their opinion and you can't really argue with a person's opinion now can you?
Not everyone is as fortunate as us to get to go to Universal all the time. And most people don't know half of the things we all do about theme parks. Just because a ride or show is played out to us does not mean that it's time for it to go. Many people walking through those arches are doing so for the first time and are still very impressed by everything Universal has to offer. So just because you have seen something 1000 times and are sick of it doesn't mean it isn't of value to other people. If everything at Universal was an E-ticket attraction, there would be serious issues with crowd flow. Twister is just something to eat people up and spit them back out twenty minutes later, and with that in mind, it does a pretty good job of it. For a simple special effects demonstration, it could be a lot worse.
