So - I have to say that the "Heights" phobia would be in full effect on gondolas, but not sure that "enclosed spaces" effect would be. It's not like going in a closet or elevator - you have a 360 degree view around you. If you have THAT bad a phobia of enclosed spaces - wouldn't you be unable to ride on just about every Disney ride because they are "trapping" you in the ride vehicles? And yes, I understand phobias because I have a wierd phobia of fear being over water or perhaps it is falling into water. Bridges and piers are especially bad for me - and the height doesn't really matter as I can be 4 feet above the water and still get a panic attack. It's extra weird because I have no fear of being IN the water when I want to go in and I love to swim. Soarin' is the hardest ride at WDW for me to ride because certain scenes flying over water make me really tense. It's also a big reason I don't really enjoy
DCL. (or any cruise for that matter)
By the way - people with phobias CAN also overcome their phobias. They aren't rational fears, and as rational humans we can learn to control and overcome phobias. I myself have gotten much better. I have no problems riding gondolas up the sides of mountains, but it's quite possible that I will have a hard time with the Pop/AoA leg of the gondolas - but if I have need to ride it I will likely do it. I ride Soarin', I've been on a cruise. BUT - it's always a fight when the irrational tries to overcome the rational.