Don't let that shy you away from agility. it's totally NORMAL and in fact even if a dog isn't afraid they should be properly desensitized and trained for each obstacle. A dog not fearful can do something stupid at first and that can create major fears to overcome after. It's just part of the process for agility, the first set of classes (and then some) is really getting the dog used to things slowly.
Also, sometimes in these sorts of settings they don't intro them properly. They just want the dog "doing things" which isn't really ideal at all. for example, in all my classes we never introduce ad go to a full tunnel. you fold it up real small and get them used to that then slowly make it longer (in a straight line) then after lots of practice you start adding small angles in the tunnel. Same with the jumps, when you train you start by walking over them yourself WITH the dog and then you walk right beside it with the dog so they can't skip out.
FUn to try different sports though. I've done flyball, agility, dock diving. Did a short demo for nose work too and did a hunt training class. I dable in many sports For Penny I will concentrate on Dock Diving (she LOVEES it), agility in the summers and Rally-O (we start classes next week). I may do a nose work class with the old man (Rocky) as he loves to work for food.