Frankly speaking, if you dislike cetaceans in captivity, fine. They do have special requirements just like all so called 'advanced' species. The captivity debate is a complex issue based more on personal morals than concrete, unchangeable facts. Arguing about whether it is absolutely good or absolutely bad to keep them in captivity will never amount to anything.
With that said, Sea Shepherd is an animal rights group that, just like PETA, is not above bending the truth and making outright lies. Taiji dolphins generally stay in east Asia, with no dolphins from the drive captures in continental North America, Oceania, or western Europe.
Sea Shepherd however, regularly acts as if all captive dolphins are from Taiji, and repeats it as if repetition makes something true.
The fact is, nothing Sea Shepherd says could ever be considered educational or helpful to dolphin trainers because dolphin trainers, especially the kind that go out and actively take part in groups like IMATA already know far more about their own animals than anyone from Sea Shepherd ever could.