"Orcas at SeaWorld are forced to perform daily"
First, you can't force a 4-ton animal to anything. The training techniques used are all based on positive reinforcement. Food deprivation is known in the training world as the worst technique ever invented. Orcas have daily meals like you and me, each orca has a specific diet, regardless of shows. The fish they receive at the show is part of the “positive reinforcement”, which only serves to show the animal that it performed the behavior correctly.
Captive orcas do not need to hunt, which is about 75% of their activity in the wild, so presentations are extremely important for the physical and mental well-being of animals. However, if the animal does not want to do the show, it will not be obliged, and the show will be canceled