I have taken both my girls to Disney even before that age. DD4 turned one on her first trip to DLR, and DD2's first trip to DLR was at 10 months. DD4 first went to WDW at 1 1/2, and we celebrated DD2's first birthday at WDW. We've taken several other trips since those.
Will they remember their earliest trips? No. But DD4 remembers stuff from her trips when she was 2 and on. I know I remember them, and they had so much fun at the time! I'm so glad we went. I used to think we would never take littles to Disney, but I couldn't wait once I had my first. I'm so relieved I didn't.
I do understand it's a much longer trip for you. Honestly, that would be more a factor for me than deciding if WDW at that age is worth it. For instance, we want to take our girls lots of places, Europe, for example. But we decided to wait until they are older not because we think it's not worth taking them when they won't remember, but because they struggle with our cross country flights, so we know longer would be that much harder for them, and therefor, us. When they get better at handling a flight to FL or to visit our family in NY and PA, then we will feel ready to go further. That would be my only concern in your case, not if WDW is worth it with a young child.
Eta: my DD4 is much better now, so we are just waiting for DD2 to get better. Your DD is at an age where she would likely travel pretty well.